CONSTRUCTION AND BOUNDS ON LINEAR CODES WITH PERSCRIBED HULL DIMENSION OVER FINITE FIELD
By
Mr. Todsapol MANKEAN
A Thesis Proposal Submitted in Partial Fulfillment of the Requirements for Doctor of Philosophy (MATHEMATICS)
Department of MATHEMATICS Graduate School, Silpakorn University
Academic Year 2020
Copyright of Graduate School, Silpakorn University
CONSTRUCTIONS AND BOUNDS ON LINEAR CODES WITH PRESCRIBED HULL DIMENSION OVER FINITE FIELDS
การสร้างและค่าขอบเขตของรหัสเชิงเส้นบนฟีลด์จ ากัดซึ่งก าหนดมิติของเปลือกหุ้ม
โดย
Mr.Todsapol MANKEAN
โครงร่างวิทยานิพนธ์นี้เป็นส่วนหนึ่งของการศึกษาตามหลักสูตรปรัชญาดุษฎีบัณฑิต สาขาวิชาคณิตศาสตร์ แบบ 2.1 ปรัชญาดุษฎีบัณฑิต นานาชาติ
ภาควิชาคณิตศาสตร์
บัณฑิตวิทยาลัย มหาวิทยาลัยศิลปากร ปีการศึกษา 2563
ลิขสิทธิ์ของบัณฑิตวิทยาลัย มหาวิทยาลัยศิลปากร
CONSTRUCTION AND BOUNDS ON LINEAR CODES WITH PERSCRIBED HULL DIMENSION OVER FINITE FIELD
By
Mr. Todsapol MANKEAN
A Thesis Proposal Submitted in Partial Fulfillment of the Requirements for Doctor of Philosophy (MATHEMATICS)
Department of MATHEMATICS Graduate School, Silpakorn University
Academic Year 2020
Copyright of Graduate School, Silpakorn University
CONSTRUCTIONS AND BOUNDS ON LINEAR CODES WITH PRESCRIBED HULL DIMENSION OVER FINITE FIELDS
Title CONSTRUCTION AND BOUNDS ON LINEAR CODES WITH PERSCRIBED HULL DIMENSION OVER FINITE FIELD
By Todsapol MANKEAN
Field of Study (MATHEMATICS)
Advisor Associate Professor SOMPHONG JITMAN , Ph.D.
Graduate School Silpakorn University in Partial Fulfillment of the Requirements for the Doctor of Philosophy
(Associate Professor Jurairat Nunthanid, Ph.D.) Dean of graduate school Approved by
(Assistant Professor Ratana Srithus , Ph.D.) Chair person
(Associate Professor SOMPHONG JITMAN , Ph.D.)
Advisor
(Professor Patanee Udomkavanich , Ph.D.) External Examiner
Title CONSTRUCTIONS AND BOUNDS ON LINEAR CODES WITH PRESCRIBED HULL DIMENSION OVER FINITE FIELDS By Todsapol MANKEAN
Title CONSTRUCTIONS AND BOUNDS ON LINEAR CODES WITH PRESCRIBED HULL DIMENSION OVER FINITE FIELDS
By Todsapol MANKEAN
C
60305805 : MAJOR : MATHEMATICS
KEY WORDS : LINEAR CODES / BOUNDS / OPTIMAL CODES / HULLS OF LINEAR CODES / EUCLIDEAN INNER PRODUCT / HERMITIAN INNER PRODUCT
TODSAPOL MANKEAN : CONSTRUCTIONS AND BOUNDS ON LINEAR CODES WITH PRESCRIBED HULL DIMENSION OVER FINITE FIELDS. THESIS ADVISOR : ASSOCIATE PROFESSOR SOMPHONG JINMAN, Ph.D.
Due to their wide applications, hulls of linear codes have been of interest and extensively studied. In this thesis, bounds on the parameters and constructions of optimal linear codes with hull dimension one over small finite fields have been focused on. For all positive integers
𝑛 ≥ 3and
𝑞 ∈ {2,3}, optimal linear
[𝑛, 2, 𝑑]𝑞codes with Euclidean hull dimension one are constructed. Moreover, for
𝑞 = 2, the enumeration of such optimal codes is given up to equivalence. For all lengths
𝑛 ≥ 3such that
𝑛 ≡ 1, 2, 4 (mod 5), optimal quaternary linear
[𝑛, 2]4
codes with Hermitial hull dimension one are constructed. For positive integers
𝑛 ≡0, 3 (mod 5)
, good lower and upper bounds on the minimum weight of quaternary
[𝑛, 2, 𝑑]4codes with Hermitian hull dimension one are given as well as some illustrative examples.
D
Acknowledgements
This thesis has been completed by the involvement of people about whom I would like to mention here.
I would like to express my deep gratitude to my thesis advisor, Associate Professor Dr. Somphong Jitman, for his help and support in all stages of my thesis studies.
I would like to thank to my thesis committees, Assistant Professor Dr. Ratana Srithus and Professor Dr. Patanee Udomkavanich, for comments and suggestions.
I would like to thank all the teachers who have instructed and taught me for valuable knowledge.
I would like to thank the Development and Promotion of Science and Technology Talents Project (DPST) for financial support throughout my undergraduate and graduate studies.
Finally, I would like to thank my family, my friends and those whose names are not mentioned here but have greatly inspired and encouraged me throughout the period of this research.
Todsapol MANKEAN
E
Table of Contents
Page Abstract……… C Acknowledgements………... D Chapter
1. Introduction………... 1
2. Preliminaries………. 3
2.1 Linear Codes over Finite Fields……….. 3
2.2 Hulls of Linear Codes………. 4
2.3 Constructions and Bounds……….. 7
3. Optimal Binary Linear Codes with Euclidean Hull Dimension One……… 10
3.1 Basic Concepts……… 10
3.2
𝑛 ≡ 1 (mod 6)………. 12
3.3
𝑛 ≡ 3 (mod 6)……… 15
3.4
𝑛 ≡ 5 (mod 6)……… 18
3.5
𝑛 ≡ 0,2,4 (mod 6)………. 20
4. Optimal Ternary Linear Codes with Euclidean Hull Dimension One………. 26
4.1 Basic Concepts……… 26
4.2
𝑛 ≡ 1 (mod 4)………. 28
4.3 𝑛 ≡ 2 (mod 4)
……… 30
4.4
𝑛 ≡ 3 (mod 4)……… 32
4.5
𝑛 ≡ 0 (mod 4)………... 33
5. Quaternary Linear Codes with Hermitian Hull Dimension One……….... 36
5.1 Basic Concepts……… 36
F
5.2 Optimal Quaternary Linear Codes with Hermitian
Hull Dimension One with
𝑛 ≡ 1, 2, 4 (mod 5)………. 39
5.3 Bounds on
𝐷4𝐻(𝑛, 2,1)with
𝑛 ≡ 0, 3 (mod 5)………... 46
6. Conclusion ……….. 49
References………. 52
Publications………... 55
Biography………. 56
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T`2b+`B#2/ ?mHH /BK2MbBQM M/ i?2B` TTHB+iBQMbX
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`2 ;Bp2M 7Q` TQbBiBp2 BMi2;2`b n≡0,3 (mod 5)X
k
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S`2HBKBM`B2b
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>KKBM; r2B;?i Q7 HBM2` +Q/2 C Bb
d= wt(C) = min{wt(c)|wt(c)∈C\ {0}},
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"
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G=
⎡
⎣1 0 1 0 1 0 1 1 1 1
⎤
⎦.
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C⊥E :={u∈Fnq |⟨u,c⟩E= 0 7Q` HH c∈C} U`2bTX-C⊥H :={u∈Fnq |⟨u,c⟩H= 0 7Q` HH c∈C})
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Y|In−k
"
Bb bB/ iQ #2 BM biM/`/ 7Q`KUb22 (Re- .2}MBiBQM 9X8Xj)VX
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Ki`Bt Q7 M [n, k]q@+Q/2 C- i?2M i?2 biM/`/ 7Q`K ;2M2`iQ` Ki`Bt Q7 C⊥E Bb H = [−AT|In−k]X
1tKTH2 kXkXkX G2iC #2 HBM2` +Q/2 Q7 H2M;i? 5Qp2` F2 rBi? ;2M2`iQ` Ki`Bt
G=
⎡
⎣1 0 1 0 1 0 1 1 1 1
⎤
⎦,
h?2M C ={00000,10101,01111,11010} ?b T`K2i2`b [5,2,3]2X "v h?2Q`2K kXkXR- r2 ?p2 i?i
H =
⎡
⎢⎢
⎢⎣
1 1 1 0 0 0 1 0 1 0 1 1 0 0 1
⎤
⎥⎥
⎥⎦
Bb T`Biv@+?2+F Ki`Bt 7Q` C M/ ?2M+2-
C⊥E ={00000,10011,11001,01010,01111,11100,10110,00101}.
"v i?2 /2}MBiBQM Q7 i?2 ?mHH- r2 ?p2 >mHH(C) = {00000,01111}X 8
1tKTH2 kXkXjX G2i F4 ={0,1,ω,ω2 =ω+ 1} M/ H2iC #2 HBM2` +Q/2 Q7 H2M;i?
5 Qp2`F4 rBi? ;2M2`iQ` Ki`Bt G=
⎡
⎣1 0 1 ω ω2 0 1 0 1 ω
⎤
⎦.
h?2M C ?b T`K2i2`b [5,2,4]4."v h?2Q`2K kXkXR- C⊥H ?b ;2M2`iQ` Ki`Bt
H =
⎡
⎢⎢
⎢⎣
1 0 1 0 0 ω 1 0 1 0 ω2 ω 0 0 1
⎤
⎥⎥
⎥⎦.
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h?2 ?mHH /BK2MbBQM Q7 HBM2` +Q/2 +M #2 /2i2`KBM2/ mbBM; Bib ;2M2`iQ` Ki`Bt BM (3) b 7QHHQrbX
S`QTQbBiBQM kXkX9 U(3- S`QTQbBiBQMb jXR)VX G2i C #2 HBM2` [n, k, d]q +Q/2 rBi?
;2M2`iQ` Ki`Bt GX h?2M rank(GGT) Bb BM/2T2M/2Mi Q7 G M/
rank(GGT) =k−dim(Hull(C)) =k−dim(Hull(C⊥E)).
AM //BiBQM- B7 q Bb b[m`2- i?2M
rank(GG†) =k−dim(HullH(C)) = k−dim(HullH(C⊥H)).
1tKTH2 kXkX8X 6`QK 1tKTH2 kXkXk- r2 ?p2 k = 2, G=
⎡
⎣1 0 1 0 1 0 1 1 1 1
⎤
⎦ M/
GGT =
⎡
⎣1 0 0 0
⎤
⎦.
h?Bb BKTHB2b i?i rank(GGT) = 1X "v S`QTQbBiBQM kXkX9- Bi 7QHHQrb i?i dim(Hull(C)) = k−rank(GGT)
= 2−1 = 1.
>2M+2- dim(Hull(C)) = 1X
e
1tKTH2 kXkXeX 6`QK 1tKTH2 kXkXj- r2 ?p2 k = 2- G=
⎡
⎣1 0 1 ω ω2 0 1 0 1 ω
⎤
⎦ M/
GG†=
⎡
⎣0 0 0 1
⎤
⎦.
h?Bb BKTHB2b i?i rank(GG†) = 1X "v S`QTQbBiBQM kXkX9- Bi +M #2 /2/m+2/ i?i
dim(HullH(C)) = k−rank(GG†)
= 2−1 = 1.
h?2`27Q`2-dim(HullH(C)) = 1X
kXj *QMbi`m+iBQMb M/ "QmM/b
lbBM; i?2 MHvbBb QM ;2M2`iQ` Ki`Bt Q7 HBM2` +Q/2b BM (RN)- r2 ?p2 i?2 7QH@
HQrBM; `2bmHibX 6Q` M [n,2]q +Q/2 rBi? ;2M2`iQ` Ki`Bt
G=
⎡
⎣a11 a12 · · · a1n
a21 a22 · · · a2n
⎤
⎦,
r2 r`Bi2
G=
⎡
⎣α1 α2
⎤
⎦, UkXRV
r?2`2 α1 =!
a11 a12 · · · a1n
"
M/ α2 =!
a21 a22 · · · a2n
"
X Hi2`MiBp2Hv- #v b2iiBM; βl=
⎡
⎣a1l
a2l
⎤
⎦ 7Q` 1≤l ≤n-G +M #2 pB2r2/ b
G=!
β1 β2 · · · βn
"
. UkXkV
6Q`i, j ∈Fq- H2i
Sij :=|{l∈{1,2, . . . , n} |βl =
⎡
⎣i j
⎤
⎦}|. UkXjV
d
1tKTH2 kXjXRX G2iC M/ C′ #2 i2`M`v HBM2` +Q/2b Q7 H2M;i? 7;2M2`i2/ #v G=
⎡
⎣1 1 0 1 1 2 2 0 0 1 1 1 1 1
⎤
⎦
M/
G′ =
⎡
⎣1 1 0 1 1 2 2 1 1 1 0 0 1 1
⎤
⎦.
q2 b22 i?i G M/ G′ `2 /2i2`KBM2/ #v S10 = 2, S01 = 1, S11 = 2, S21 = 2, M/
Sij = 0Qi?2`rBb2X Ai Bb 2bBHv b22M i?i C M/ C′ `2 2[mBpH2Mi #v i?2 T2`KmiiBQM (1 4)(2 5)X
_2K`F kXjXkX h?2 ;2M2`iQ` Ki`B2b /2i2`KBM2/ #v Sij :=|{l ∈{1,2, . . . , n} |βl=
⎡
⎣i j
⎤
⎦}|
;2M2`i2 2[mBpH2Mi HBM2` +Q/2bX h?2 2[mBpH2M+2b `2 BM/m+2/ #v T2`KmiiBQM QM {1,2, . . . , n}.
h?2 :`B2bK2` "QmM/ BM (N) Bb TTHB2/ BM i?Bb rQ`FX
h?2Q`2K kXjXj U:`B2bK2` "QmM/- (N- h?2Q`2K kXdX9)VX G2i q #2 T`BK2 TQr2` M/
H2i n- k M/ d #2 TQbBiBp2 BMi2;2`bX A7 i?2`2 2tBbib M [n, k, d]q +Q/2- i?2M n ≥
*k−1 i=0
+d qi
, .
h?2 KBMBKmK >KKBM; r2B;?i Q7 HBM2` +Q/2b Bb BKTQ`iMi iQ /2i2`KBM2 i?2 2``Q`@+Q``2+iBM; +T#BHBiv Q7 +Q/2bX AM i?Bb i?2bBb- r2 7Q+mb QM i?2 KtBKmK Q7 i?2 KBMBKmK >KKBM; r2B;?i Q7 HBM2` +Q/2bX 6Q` T`BK2 TQr2` q- TQbBiBp2 BMi2;2`b n, k M/ MQM@M2;iBp2 BMi2;2` ℓ- H2i
Dq(n, k,ℓ) := max{d|∃[n, k, d]q +Q/2 rBi? dim(Hull(C)) =ℓ} M/
DHq(n, k,ℓ) := max{d|∃[n, k, d]q +Q/2 rBi? dim(HullH(C)) = ℓ}.
"b2/ QM i?2 :`B2bK2` "QmM/- i?2 7QHHQrBM; mTT2` #QmM/b QMDq(n, k,ℓ)M/DHq(n, k,ℓ) +M #2 /2`Bp2/ BM i?2 M2ti H2KKX
3
G2KK kXjX9X G2i q #2 T`BK2 TQr2` M/ H2i n, k M/ ℓ #2 BM2;2`b bm+? i?i 1≤k≤n M/ 0≤ℓX h?2M
Dq(n, k,ℓ)≤
-(q−1)qk−1n (qk−1)
.
M/
DqH(n, k,ℓ)≤
-(q−1)qk−1n (qk−1)
. B7 q Bb b[m`2.
S`QQ7X 6`QK i?2 :`B2bK2` "QmM/ BM h?2Q`2K kXjXj- 7Q` Mv HBM2` [n, k, d]q +Q/2- r2
?p2
n ≥
*k−1 i=0
+d qi
,
≥d
*k−1 i=0
1
qi = d(qk−1) (q−1)qk−1. Ai 7QHHQrb i?i
d≤
-(q−1)qk−1n (qk−1)
. .
>2M+2- Dq(n, k,ℓ)≤/
(q−1)qk−1n (qk−1)
0 b /2bB`2/X
aBM+2 i?2 #Qp2 T`QQ7 Bb BM/2T2M/2Mi Q7 i?2 BMM2` T`Q/m+i-DqH(n, k,ℓ)≤/
(q−1)qk−1n (qk−1)
0
7QHHQrb bBKBH`HvX
AM i?Bb i?2bBb- r2 7Q+mb QM Dq(n, k,1) M/ DqH(n, k,1)X h?2 /2iBHb `2 /Bb+mbb2/
BM i?2 7QHHQrBM; +?Ti2`bX
N
*?Ti2` j
PTiBKH "BM`v GBM2` *Q/2b rBi?
1m+HB/2M >mHH .BK2MbBQM PM2
AM i?Bb +?Ti2`- r2 7Q+mb QM +QMbi`m+iBQM Q7 #BM`v HBM2` +Q/2b rBi? ?mHH /BK2MbBQM QM2X 6Q` 2+? BMi2;2` n ≥ 3- M QTiBKH [n,2]2 +Q/2 rBi? ?mHH /BK2MbBQM QM2 Bb +QM@
bi`m+i2/X JQ`2Qp2`- i?2 2MmK2`iBQM Q7 bm+? QTiBKH +Q/2b Bb ;Bp2M mT iQ 2[mBpH2M+2X
jXR "bB+ *QM+2Tib
6`QK i?2 b2imT BM am#b2+iBQM kXj U+X7X (RN)V- HBM2` [n,2]2 +Q/2 C rBi? ;2M2`iQ`
Ki`Bt
G=
⎡
⎣α1
α2
⎤
⎦ UjXRV
rBi? α1 = %
a11 a12 · · · a1n
&
M/ α2 = %
a21 a22 · · · a2n
&
+M #2 pB2r2/ Q7 i?2 7Q`K C = {0,α1,α2,α1 +α2}. 6`QK UkXjV- r2 ?p2 α1 = %
a11 a12 · · · a1n
&
M/
α2 =%
a21 a22 · · · a2n
&
M/ Bi Bb MQi /B{+mHi iQ b22 i?i
ri(α1) =S10+S11,ri(α2) =S01+S11,ri(α1+α2) =S10+S01.
Ry
>2M+2-
wt(C) = min{ri(α1),ri(α2),ri(α1+α2)}
= min{S10+S11, S01+S11, S10+S01}. UjXkV 6`QK UjXRV- r2 ?p2
GGT =
⎡
⎣S10+S11 S11
S11 S01+S11
⎤
⎦(mod 2). UjXjV
1tKTH2 jXRXRX G2i C #2 i?2 #BM`v HBM2` +Q/2 Q7 H2M;i? 5 rBi? ;2M2`iQ` Ki`Bt
G=
⎡
⎣1 0 0 1 1 0 1 1 0 1
⎤
⎦
h?2M S00 = 0, S10 = 2, S01 = 2 M/ S11 = 1 r?B+? BKTHB2b i?i S10 +S11 = 3 M/
S01+S11= 3 "v UjXjV- Bi 7QHHQrb i?i
GGT =
⎡
⎣1 1 1 1
⎤
⎦
r?B+? BKTHB2b i?i rank(GGT) = 1 M/ dim(Hull(C)) = 2− rank(GGT) = 1 #v S`QTQbBiBQM kXkX9X
_2K`F jXRXkX h?2 #BM`v +Q/2b /2i2`KBM2/ #v
(S01, S10, S11)∈{(a, b, c),(b, a, c),(c, b, a),(a, c, b),(b, c, a),(c, a, b)}
`2 2[mBpH2MiX h?Bb 7QHHQrb 7`QK i?2 7+i i?i
⎡
⎣α1 α2
⎤
⎦-
⎡
⎣α2 α1
⎤
⎦-
⎡
⎣α1+α2 α2
⎤
⎦-
⎡
⎣ α1 α1+α2
⎤
⎦-
⎡
⎣α1+α2 α1
⎤
⎦- M/
⎡
⎣ α2 α1+α2
⎤
⎦
;2M2`i2 i?2 bK2 +Q/2X
1tKTH2 jXRXjX "v _2K`F jXRXk- H2i a= 2, b = 0 M/ c= 3X h?2M
(S01, S10, S11)∈{(2,0,3),(0,2,3),(3,0,2),(2,3,0),(0,3,2),(3,2,0)}.
RR
6Q` (S01, S10, S11) = (2,0,3)- r2 ?p2 i?i α1 = 00111 M/ α2 = 11111X G2i C #2 HBM2` +Q/2 rBi? ;2M2`iQ` Ki`Bt
G=
⎡
⎣α1
α2
⎤
⎦=
⎡
⎣0 0 1 1 1 1 1 1 1 1
⎤
⎦.
h?2M C ={00000,00111,11111,11000}X "v _2K`F jXRXk- r2 ?p2 i?i
⎡
⎣α2
α1
⎤
⎦=
⎡
⎣0 0 1 1 1 1 1 0 0 0
⎤
⎦/2i2`KBM2/ #v (S01, S10, S11) = (0,2,3)
⎡
⎣α1+α2
α2
⎤
⎦=
⎡
⎣1 1 0 0 0 1 1 1 1 1
⎤
⎦/2i2`KBM2/ #v (S01, S10, S11) = (3,0,2)
⎡
⎣ α1
α1+α2
⎤
⎦=
⎡
⎣0 0 1 1 1 1 1 0 0 0
⎤
⎦/2i2`KBM2/ #v (S01, S10, S11) = (2,3,0)
⎡
⎣α1+α2
α1
⎤
⎦=
⎡
⎣1 1 0 0 0 0 0 1 1 1
⎤
⎦/2i2`KBM2/ #v (S01, S10, S11) = (0,3,2),M/
⎡
⎣ α2
α1+α2
⎤
⎦=
⎡
⎣1 1 1 1 1 1 1 0 0 0
⎤
⎦/2i2`KBM2/ #v (S01, S10, S11) = (3,2,0)
;2M2`i2 HBM2` +Q/2 *X
6Q` #BM`v HBM2` +Q/2b rBi? /BK2MbBQM irQ M/ ?mHH /BK2MbBQM QM2- i?2 mTT2`
#QmM/ BM G2KK kXjX9 +M #2 bBKTHB}2/ b D2(n,2,1)≤
-2n 3
.
. UjX9V
lbBM; i?2 MQiiBQMb #Qp2- i?2 2t+i pHm2 Q7D2(n,2,1)+M #2 /2`Bp2/ iQ;2i?2` rBi?
i?2 2MmK2`iBQM Q7 QTiBKH [n,2]2 +Q/2b b 7QHHQrbX
jXk n ≡ 1 (mod 6)
AM i?2 7QHHQrBM; i?2Q`2K- r2 ;Bp2 +QMbi`m+iBQMb Q7 QTiBKH [n,2,12n
3
2]2 +Q/2b Q7 bm+? H2M;i?b rBi? ?mHH /BK2MbBQM QM2 7Q` HH n ≡1 (mod 6)X
Rk
h?2Q`2K jXkXRX G2i n ≥3 #2 M BMi2;2`X A7 n ≡1 (mod 6)- i?2M D2(n,2,1) =
-2n 3
.
M/ i?2`2 2tBbib mMB[m2 UmT iQ 2[mBpH2M+2V QTiBKH 3
n,2,12n
3
24
2 +Q/2 rBi? ?mHH /BK2MbBQM QM2X
S`QQ7X bbmK2 i?i n ≡1 (mod 6)X h?2M n = 6t+ 1 7Q` bQK2 TQbBiBp2 BMi2;2` t M/
12n
3
2 =/
2(6t+1) 3
0= 4tX
6Q` i?2 2tBbi2M+2- #v UjX9V- Bi bm{+2b iQ b?Qr i?i i?2`2 2tBbib M [n,2,4t]2 +Q/2 rBi? ?mHH /BK2MbBQM QM2X G2i C #2 HBM2` +Q/2 rBi? ;2M2`iQ` Ki`Bt G /2}M2/ BM UjXRV bm+? i?i (S01, S10, S11) = (2t,2t,2t+ 1)X h?2MC Bb M [n,2, d]2 +Q/2- r?2`2
d= min{S01+S11, S10+S11, S10+S01}
= min{4t+ 1,4t+ 1,4t}
= 4t #v UjXkV.
6`QK UjXjV- r2 ?p2
GGT =
⎡
⎣1 1 1 1
⎤
⎦
r?B+? BKTHB2b i?i rank(GGT) = 1X q2 i?2`27Q`2 ?p2 dim(Hull(C)) = 1 #v S`QTQ@
bBiBQM kXkX9X
6Q` i?2 mMB[m2M2bb- r2 }`bi b?Qr i?i S01+S10+S11 = nX amTTQb2 i?i i?2`2 2tBbib M [n,2,4t]2 +Q/2 rBi? ?mHH /BK2MbBQM QM2 M/S00>0X h?2M
S01+S10+S11 ≤n−1 = 6t.
aBM+2min{S10+S11, S01+S11, S10+S01}= 4t Bb `2[mB`2/- i?2 QMHv TQbbB#H2 +?QB+2 Q7 (S01, S10, S11) Bb (2t,2t,2t)X AM i?Bb +b2- r2 ?p2
GGT =
⎡
⎣0 0 0 0
⎤
⎦
Rj
#v UjXjVX "v S`QTQbBiBQM kXkX9- r2 i?2`27Q`2 ?p2dim(Hull(C)) = 2̸= 1- +QMi`/B+@
iBQMX >2M+2- n=S01+S10+S11X
Ai `2KBMb iQ 7Q+mb QM (S01, S10, S11) biBb7vBM; S01+S10+S11 =n = 6t+ 1 M/
min{S10+S11, S01+S11, S10+S01}= 4tX Ai 7QHHQrb i?i
(S01, S10, S11)∈{(2t,2t,2t+ 1),(2t,2t+ 1,2t),(2t+ 1,2t,2t), (2t−1,2t+ 1,2t+ 1),(2t+ 1,2t−1,2t+ 1), (2t+ 1,2t+ 1,2t−1)}.
q2 +QMbB/2` i?2 7QHHQrBM; 2 +b2bX
*b2 RX (S01, S10, S11)∈{(2t,2t,2t+ 1),(2t,2t+ 1,2t),(2t+ 1,2t,2t)}."v UjXjV- i?2 +Q``2bTQM/BM; Ki`B+2b GGT `2 Q7 i?2 7Q`Kb
⎡
⎣1 1 1 1
⎤
⎦-
⎡
⎣1 0 0 0
⎤
⎦- M/
⎡
⎣0 0 0 1
⎤
⎦-
`2bT2+iBp2HvX AM i?2b2 +b2b- r2 ?p2 rank(GGT) = 1 r?B+? BKTHB2b i?i i?2`2 ?mHH /BK2MbBQMb `2 QM2 #v S`QTQbBiBQM kXkX9X 6`QK _2K`F jXRXk- i?2b2 +Q/2b `2 2[mBp@
H2MiX
*b2 kX (S01, S10, S11)∈{(2t−1,2t+ 1,2t+ 1),(2t+ 1,2t−1,2t+ 1),(2t+ 1,2t+ 1,2t−1)}X 6`QK UjXjV- Bi Bb 2bBHv b22M i?i
GGT =
⎡
⎣0 1 1 0
⎤
⎦.
>2M+2- rank(GGT) = 2 r?B+? BKTHB2b i?i i?2 +Q/2b `2 G*. #v S`QTQbBiBQM kXkX9X
1tKTH2 jXkXkX G2i t = 2X "v h?2Q`2K 3.2.1- r2 ?p2 i?i (S01, S10, S11) = (2t,2t,2t+ 1) = (4,4,5)X G2i C #2 i?2 #BM`v HBM2` +Q/2 Q7 H2M;i?13/2i2`KBM2/ #v i?2 i`BTH2 (4,4,5) rBi? ;2M2`iQ` Ki`Bt
G=
⎡
⎣0 0 0 0 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 0 0 1 1 1 1 1
⎤
⎦.
R9
"v UjXjV- Bi 7QHHQrb i?i
GGT =
⎡
⎣1 1 1 1
⎤
⎦
r?B+? BKTHB2b i?i rank(GGT) = 1 M/ dim(Hull(C)) = 2− rank(GGT) = 1 #v S`QTQbBiBQM kXkX9X h?2M C Bb M QTiBKH[13,2,8]2 +Q/2 rBi? ?mHH /BK2MbBQM QM2X
jXj n ≡ 3 (mod 6)
L2ti- r2 b?Qr i?i i?2`2 /Q2b MQi 2tBbi [n,2,12n
3
2]2 +Q/2b rBi? ?mHH /BK2MbBQM QM2 7Q` HH n≡3 (mod 6)X Gi2`- r2 ;Bp2 +QMbi`m+iBQMb Q7 QTiBKH [n,2,12n
3
2−1]2 +Q/2b Q7 bm+? H2M;i?b rBi? ?mHH /BK2MbBQM QM2X
h?2Q`2K jXjXRX G2i n ≥3 #2 M BMi2;2`X A7 n ≡3(mod 6)- i?2M D2(n,2,1) =
-2n 3
.
−1.
AM i?Bb +b2- i?2`2 2tBbib mMB[m2 UmT iQ 2[mBpH2M+2V QTiBKH [3,2,1]2 +Q/2 rBi? ?mHH /BK2MbBQM QM2 M/ i?2`2 `2 irQ UmT iQ 2[mBpH2M+2V QTiBKH 3
n,2,12n
3
2−14
2 +Q/2b rBi? ?mHH /BK2MbBQM QM2 7Q` HH n >3X
S`QQ7X bbmK2 i?in ≡3(mod 6)X h?2Mn = 6t+ 3 7Q` bQK2 BMi2;2`t≥0X "v UjX9V- r2 ?p2
D2(n,2,1)≤ -2n
3 .
=
-2(6t+ 3) 3
.
= 4t+ 2.
amTTQb2 i?2`2 2tBbib M3
n,2,12n
3
2= 4t+ 24
2 +Q/2 rBi? ?mHH /BK2MbBQM QM2X h?2M-
#v UjXkV- r2 ?p2 wt(C) = min{S01+S11, S10+S11, S10+S01} = 4t+ 2 M/ S01+ S10+S11≤n = 6t+ 3X >2M+2- i?2 QMHv TQbbB#H2 +?QB+2 Q7(S01, S10, S11)Bb(2t+ 1,2t+ 1,2t+ 1)X "v UjXjV- r2 ?p2
GGT =
⎡
⎣0 1 1 0
⎤
⎦.
"v S`QTQbBiBQM kXkX9- Bi 7QHHQrb i?i dim(Hull(C)) = 0 ̸= 1- +QMi`/B+iBQMX >2M+2- i?2`2 /Q2b MQi 2tBbi M 3
n,2,12n
3
24
2 +Q/2X R8
6Q` i?2 2tBbi2M+2 Q7 M[n,2,4t+ 1]2+Q/2 rBi? ?mHH /BK2MbBQM QM2- H2iC#2 HBM2`
+Q/2 rBi? ;2M2`iQ` Ki`Bt G pB2r2/ BM i?2 7Q`K Q7 UjXRV bm+? i?i (S01, S10, S11) = (2t,2t+ 2,2t+ 1)X h?2MC Bb M [n,2, d]2 +Q/2- r?2`2
d= min{S01+S11, S10+S11, S10+S01}
= min{4t+ 1,4t+ 3,4t+ 2}
= 4t+ 1 #v UjXkV.
6`QK UjXjV- r2 ?p2
GGT =
⎡
⎣1 1 1 1
⎤
⎦
r?B+? BKTHB2b i?i rank(GGT) = 1X b /2bB`2/- r2 ?p2 dim(Hull(C)) = 1 #v S`QTQbBiBQM kXkX9X
hQ /2i2`KBM2 i?2 MmK#2` Q7[n,2,4t+ 1]2 +Q/2b rBi? ?mHH /BK2MbBQM QM2- r2 +HBK i?i S01+S10+S11=nX amTTQb2 i?i S00>0X h?2M
S01+S10+S11≤n−1 = 6t+ 2.
aBM+2min{S10+S11, S01+S11, S10+S01}= 4t+1- i?2 TQbbB#H2 +?QB+2b Q7(S01, S10, S11)
`2 (2t,2t+ 1,2t+ 1)- (2t+ 1,2t+ 1,2t)- M/(2t+ 1,2t,2t+ 1)X "v UjXjV- i?2 Ki`Bt GGT Bb Q7 i?2 7Q`K
⎡
⎣0 1 1 1
⎤
⎦-
⎡
⎣1 0 0 1
⎤
⎦- M/
⎡
⎣1 1 1 0
⎤
⎦-
`2bT2+iBp2HvX >2M+2- rank(GGT) = 2 r?B+? BKTHB2b i?i dim(Hull(C)) = 0 ̸= 1 #v S`QTQbBiBQM kXkX9X
LQr- Bi `2KBMb iQ 7Q+mb QM i?2 i`BTH2b (S01, S10, S11)biBb7vBM; S01+S10+S11= n= 6t+ 3 M/ min{S10+S11, S01+S11, S10+S01}= 4t+ 1X "v BMbT2+iBQM- r2 ?p2 (S01, S10, S11)∈T1∪T2∪T3- r?2`2
T1 ={(2t,2t+ 2,2t+ 1),(2t+ 2,2t,2t+ 1),(2t+ 2,2t+ 2,2t−1)}, T2 ={(2t−1,2t+ 2,2t+ 2),(2t+ 1,2t,2t+ 2),(2t+ 1,2t+ 2,2t)}, T3 ={(2t,2t+ 1,2t+ 2),(2t+ 2,2t−1,2t+ 2),(2t+ 2,2t+ 1,2t)}.
Re
"v UjXjV- i?2 Ki`B+2b GGT `2 Q7 i?2 7Q`Kb
⎡
⎣1 1 1 1
⎤
⎦-
⎡
⎣0 0 0 1
⎤
⎦- M/
⎡
⎣1 0 0 0
⎤
⎦
7Q` (S01, S10, S11) BMT1- T2- M/ T3- `2bT2+iBp2HvX Ai 7QHHQrb i?i rank(GGT) = 1 M/
i?2 +Q/2b ?p2 ?mHH /BK2MbBQM QM2 #v S`QTQbBiBQM kXkX9X 6`QK _2K`F jXRXk- i?2 +Q/2b /2i2`KBM2/ #v
(S01, S10, S11)∈{(2t,2t+ 2,2t+ 1),(2t+ 2,2t,2t+ 1),(2t+ 2,2t+ 1,2t), (2t,2t+ 1,2t+ 2),(2t+ 1,2t,2t+ 2),(2t+ 1,2t+ 2,2t)}
`2 2[mBpH2Mi- M/ i?2 +Q/2b /2i2`KBM2/ #v
(S01, S10, S11)∈{(2t+ 2,2t+ 2,2t−1),(2t−1,2t+ 2,2t+ 2), (2t+ 2,2t−1,2t+ 2)}
`2 2[mBpH2MiX aBM+2 +Q/2 BM i?2 }`bi 7KBHv +QMiBMb +Q/2rQ`/ Q7 r2B;?i 4t+ 3
#mi i?2 Hii2` /Q2b MQi- irQ +Q/2b 7`QK /Bz2`2Mi 7KBHB2b `2 MQi 2[mBpH2MiX >2M+2- i?2`2 `2 irQ UmT iQ 2[mBpH2M+2V QTiBKH3
n,2,12n
3
2−14
2 +Q/2b rBi? ?mHH /BK2MbBQM QM2 7Q` HH n > 3X 6Q` n = 3- r2 ?p2 t = 0 M/ ?2M+2- i?2 b2+QM/ 7KBHv /Q2b MQi 2tBbi r?B+? BKTHB2b i?i i?2`2 2tBbib mMB[m2 UmT iQ 2[mBpH2M+2V QTiBKH [3,2,1]2 +Q/2 rBi? ?mHH /BK2MbBQM QM2X
1tKTH2 jXjXkX G2it= 2X "v h?2Q`2K3.3.1- r2 ?p2 i?i(S01, S10, S11) = (2t,2t+
2,2t+ 1) = (4,6,5) M/ (S01, S10, S11) = (2t+ 2,2t+ 2,2t−1) = (6,6,3) BM/22/ k BM2[mBpH2Mi +Q/2bX
RX G2i C1 #2 i?2 #BM`v HBM2` +Q/2 Q7 H2M;i? 15 /2i2`KBM2/ #v i?2 i`BTH2(4,6,5) rBi? ;2M2`iQ` Ki`Bt
G1 =
⎡
⎣0 0 0 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 1 1 1 1 1
⎤
⎦.
"v UjXjV- Bi 7QHHQrb i?i
G1GT1 =
⎡
⎣1 1 1 1
⎤
⎦ Rd
r?B+? BKTHB2b i?irank(G1G1T) = 1M/dim(Hull(C)) = 2−rank(G1G1T) = 1
#v S`QTQbBiBQM kXkX9X h?2MC1 Bb M QTiBKH[15,2,9]2 +Q/2 rBi? ?mHH /BK2MbBQM QM2X
kX G2i C2 #2 i?2 #BM`v HBM2` +Q/2 Q7 H2M;i? 15 /2i2`KBM2/ #v i?2 i`BTH2(6,6,3) rBi? ;2M2`iQ` Ki`Bt
G2 =
⎡
⎣0 0 0 0 0 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 1 1 1
⎤
⎦.
"v UjXjV- Bi 7QHHQrb i?i
G2GT2 =
⎡
⎣1 0 0 0
⎤
⎦
r?B+? BKTHB2b i?irank(G2G2T) = 1M/dim(Hull(C)) = 2−rank(G2G2T) = 1
#v S`QTQbBiBQM kXkX9X h?2MC2 Bb M QTiBKH[15,2,9]2 +Q/2 rBi? ?mHH /BK2MbBQM QM2X
"v h?2Q`2K jXkXR- r2 ?p2 i?i C1 M/ C2 `2 MQi 2[mBpH2MiX
jX9 n ≡ 5 (mod 6)
AM i?2 7QHHQrBM; i?2Q`2K- r2 ;Bp2 +QMbi`m+iBQMb Q7 M QTiBKH[n,2,12n
3
2]2 +Q/2 rBi?
/BK2bBQM 2 M/ 1m+HB/2M ?mHH /BK2MbBQM QM2 Bb ;Bp2M 7Q` HH H2M;i?bn ≡5 (mod 6)X h?2Q`2K jX9XRX G2i n ≥3 #2 M BMi2;2`X A7 n ≡5(mod 6)- i?2M
D2(n,2,1) = -2n
3 .
M/ i?2`2 2tBbib mMB[m2 UmT iQ 2[mBpH2M+2V QTiBKH 3
n,2,12n
3
24
2 +Q/2 rBi? ?mHH /BK2MbBQM QM2X
S`QQ7X bbmK2 i?i n ≡5(mod 6)X h?2M n = 6t+ 5 7Q` bQK2 TQbBiBp2 BMi2;2` tX "v UjX9V- r2 ?p2
D2(n,2,1)≤ -2n
3 .
=
-2(6t+ 5) 3
.
= 4t+ 3.
R3
6Q` i?2 2tBbi2M+2 Q7 M[n,2,4t+ 3]2+Q/2 rBi? ?mHH /BK2MbBQM QM2- H2iC#2 HBM2`
+Q/2 rBi? ;2M2`iQ` Ki`Bt G pB2r2/ BM i?2 7Q`K Q7 UjXRV bm+? i?i (S01, S10, S11) = (2t+ 2,2t+ 1,2t+ 2)X h?2M C Bb M [n,2, d]2 +Q/2- r?2`2
d= min{S01+S11, S10+S11, S10+S01}
= min{4t+ 3,4t+ 3,4t+ 3}
= 4t+ 3 #v UjXkV.
6`QK UjXjV- r2 ?p2
GGT =
⎡
⎣1 0 0 0
⎤
⎦
r?B+? BKTHB2b i?i rank(GGT) = 1X >2M+2- r2 ?p2 dim(Hull(C)) = 1 #v S`QTQbB@
iBQM kXkX9X
hQ /2i2`KBM2 i?2 MmK#2` Q7[n,2,4t+ 3]2 +Q/2b rBi? ?mHH /BK2MbBQM QM2- r2 +HBK i?i S01+S10+S11=nX amTTQb2 i?i S00>0X h?2M
S01+S10+S11≤n−1 = 6t+ 4.
aBM+2 min{S10+S11, S01+S11, S10+S01} = 4t+ 3- i?2`2 `2 MQ TQbbB#H2 +?QB+2b Q7 (S01, S10, S11)- +QMi`/B+iBQMX >2M+2- S01+S10+S11=nX
Ai Bb MQi /B{+mHi iQ b22 i?i i?2 i`BTH2b(S01, S10, S11)biBb7vBM; S01+S10+S11= n= 6t+ 5 M/ min{S10+S11, S01+S11, S10+S01}= 4t+ 3 `2 BM i?2 b2i
{(2t+ 1,2t+ 2,2t+ 2),(2t+ 2,2t+ 1,2t+ 2),(2t+ 2,2t+ 2,2t+ 1)}.
"v UjXjV- i?2 +Q``2bTQM/BM; Ki`B+2b GGT `2 Q7 i?2 7Q`Kb
⎡
⎣0 0 0 1
⎤
⎦-
⎡
⎣1 0 0 0
⎤
⎦- M/
⎡
⎣1 1 1 1
⎤
⎦-
`2bT2+iBp2HvX q2 ?p2 rank(GGT) = 1 M/ i?2B` ?mHH /BK2MbBQMb `2 QM2 #v S`QTQbB@
iBQM kXkX9X h?2b2 +Q/2b `2 2[mBpH2Mi #v _2K`F jXRXkX
RN
1tKTH2 jX9XkX G2i t = 2X "v h?2Q`2K 3.4.1- r2 ?p2 i?i (S01, S10, S11) = (2t+ 2,2t+ 2,2t+ 1) = (6,6,5)X G2i C #2 i?2 #BM`v HBM2` +Q/2 Q7 H2M;i? 17/2i2`KBM2/
#v i?2 i`BTH2(6,6,5)rBi? ;2M2`iQ` Ki`Bt
G=
⎡
⎣0 0 0 0 0 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 1 1 1 1 1
⎤
⎦.
"v UjXjV- Bi 7QHHQrb i?i
GGT =
⎡
⎣1 1 1 1
⎤
⎦
r?B+? BKTHB2b i?i rank(GGT) = 1 M/ dim(Hull(C)) = 2− rank(GGT) = 1 #v S`QTQbBiBQM kXkX9X h?2M C Bb M QTiBKH[13,2,11]2 +Q/2 rBi? ?mHH /BK2MbBQM QM2X
jX8 n ≡ 0, 2, 4 (mod 6)
L2ti- r2 b?Qr i?i i?2`2 /Q2b MQi 2tBbi[n,2,12n
3
2]2 +Q/2b rBi? ?mHH /BK2MbBQM QM2 7Q` HH n ≡ 0,2,4 (mod 6)X Gi2`- r2 ;Bp2 +QMbi`m+iBQMb Q7 QTiBKH [n,2,12n
3
2−1]2
+Q/2b Q7 bm+? H2M;i?b rBi? ?mHH /BK2MbBQM QM2X
G2KK jX8XRX G2i n ≥ 3 #2 M BMi2;2`X A7 n ≡ 0,2,4 (mod 6)- i?2M i?2`2 `2 MQ [n,2,12n
3
2]2 +Q/2b rBi? ?mHH /BK2MbBQM QM2X
S`QQ7X bbmK2 i?i n ≡ 0,2,4 (mod 6)X amTTQb2 i?i i?2`2 2tBbib M [n,2,12n
3
2]2
+Q/2 C rBi? ?mHH /BK2MbBQM QM2X
6B`bi- r2 T`Qp2 i?i S10+S01+S11 =nX amTTQb2 i?i S00 >0X
*b2 AXn ≡0,2 (mod 6)X A7 7QHHQrb i?i/
2(n−1) 3
0 < 2n3 =12n
3
27Q` HHn ≡0 (mod 6)- M/ /
2(n−1) 3
0
< 2n3−1 = 12n
3
2 7Q` HH n ≡ 2 (mod 6)X aBM+2 S00 > 0- i?2`2 2tBbib M [n−1,2,12n
3
2]2 +Q/2 C′ #v TmM+im`BM; i QM2 Q7 i?2 x2`Q +QHmKMbX 6`QK UjX9V- r2
?p2 -
2n 3
.
= wt(C′)≤
-2(n−1) 3
.
<
-2n 3
. , +QMi`/B+iBQMX
ky
*b2 AAX n ≡ 4 (mod 6)X aBM+2 S00 >0- i?2`2 2tBbib M [n−1,2,12n
3
2]2 +Q/2 C′ #v TmM+im`BM; i QM2 Q7 i?2 x2`Q +QHmKMbX aBM+2 n−1≡3 (mod 6)- r2 ?p2
-2n 3
.
= wt(C′)≤D2(n−1,2,1) =
-2(n−1) 3
.
−1 = -2n
3 .
−1<
-2n 3
.
#v h?2Q`2K jXjXRX h?Bb Bb +QMi`/B+iBQMX
6`QK i?2 /Bb+mbbBQM #Qp2- r2 ?p2S10+S01+S11=nX L2ti- r2 +QMbB/2` i?2 7QHHQrBM;2 +b2bX
*b2 RX S11 Bb Q//X aBM+2 n Bb 2p2M- Bi 7QHHQrb i?i 2Bi?2` S10 Q` S01 Bb Q//X 6`QK UjXjV- r2 ?p2
GGT =
⎡
⎣0 1 1 1
⎤
⎦ Q` GGT =
⎡
⎣1 1 1 0
⎤
⎦.
AM #Qi? +b2b- rank(GGT) = 2. "v S`QTQbBiBQM kXkX9- r2 ?p2 dim(Hull(C)) = 2− rank(GGT) = 0X
*b2 kX S11 Bb 2p2MX h?2MS10 M/ S01 ?p2 i?2 bK2 T`BivX A7 S10M/ S01`2 2p2M- i?2M
GGT =
⎡
⎣0 0 0 0
⎤
⎦
#v UjXjVX A7 S10 M/ S01 `2 Q//- i?2M
GGT =
⎡
⎣1 0 0 1
⎤
⎦
#v UjXjVX AM #Qi? +b2b- dim(Hull(C)) = 2−rank(GGT)̸= 1 #v S`QTQbBiBQM kXkX9X 6`QK i?2 irQ +b2b- r2 ?p2 dim(Hull(C))̸= 1- +QMi`/B+iBQMX >2M+2- i?2`2 `2 MQ[n,2,12n
3
2]2 +Q/2b rBi? ?mHH /BK2MbBQM QM2X
h?2Q`2K jX8XkX G2i n ≥3 #2 M BMi2;2`X A7 n ≡0,2,4(mod 6)- i?2M D2(n,2,1) =
-2n 3
.
−1.
JQ`2Qp2`- i?2 7QHHQrBM; bii2K2Mib ?QH/X
RX h?2`2 2tBbib mMB[m2 UmT iQ 2[mBpH2M+2V QTiBKH 3
n,2,12n
3
2−14
2 +Q/2 rBi?
?mHH /BK2MbBQM QM2 7Q` HH n= 4 Q` n≡0,2(mod 6)X kR
kX h?2`2 `2 irQ UmT iQ 2[mBpH2M+2V QTiBKH 3
n,2,12n
3
2−14
2 +Q/2b rBi? ?mHH /B@
K2MbBQM QM2 7Q` HH n >4 bm+? i?i n≡4(mod 6)X
S`QQ7X bbmK2 i?i n ≡0,2,4(mod 6)X "v G2KK jX8XR- r2 ?p2 D2(n,2,1)≤
-2n 3
.
−1.
6B`bi- r2 Q#b2`p2 i?i i?2`2 `2 MQ i`BTH2b(S01, S10, S11)biBb7vBM;S01+S10+S11≤ n−2M/min{S10+S11, S01+S11, S10+S01}=12n
3
2−1X >2M+2- S01+S10+S11 ≥n−1X q2 +QMbB/2` i?2 7QHHQrBM; irQ +b2bX
*b2 RX n =S01+S10+S11X q2 b?Qr i?i i?2`2 `2 MQ [n,2,12n
3
2−1]2 +Q/2b rBi?
?mHH /BK2MbBQM QM2 b 7QHHQrbX
*b2 RXRX n ≡ 0(mod 6)X h?2M n = 6t 7Q` bQK2 TQbBiBp2 BMi2;2` tX h?2 i`BTH2b (S01, S10, S11) biBb7vBM; S01+S10+S11 =n = 6t M/ min{S10+S11, S01+S11, S10+ S01}=12n
3
2−1 = 4t−1`2 BM i?2 b2i
{(2t,2t+ 1,2t−1),(2t,2t−1,2t+ 1),(2t+ 1,2t,2t−1),
(2t+ 1,2t+ 1,2t−2),(2t+ 1,2t−2,2t+ 1),(2t−2,2t+ 1,2t+ 1), (2t+ 1,2t−1,2t),(2t−1,2t,2t+ 1),(2t−1,2t+ 1,2t)}.
h?2 +Q``2bTQM/BM; ;2M2`iQ` Ki`B+2b G ?p2 i?2 T`QT2`iv i?i rank(GGT) = 2 r?B+? BKTHB2b i?i dim(Hull(C)) = 0̸= 1 #v S`QTQbBiBQM kXkX9X
*b2 RXkX n ≡ 2(mod 6)X h?2M n = 6t+ 2 7Q` bQK2 TQbBiBp2 BMi2;2` tX h?2 i`BTH2b (S01, S10, S11)biBb7vBM;S01+S10+S11=n= 6t+2M/min{S10+S11, S01+S11, S10+ S01}=12n
3
2−1 = 4t `2 BM i?2 b2i
{(2t,2t,2t+ 2),(2t+ 2,2t,2t),(2t,2t+ 2,2t),(2t−2,2t+ 2,2t+ 2), (2t+ 2,2t−2,2t+ 2),(2t+ 2,2t+ 2,2t−2),(2t+ 1,2t−1,2t+ 2), (2t+ 2,2t+ 1,2t−1),(2t+ 1,2t+ 2,2t−1),(2t−1,2t+ 1,2t+ 2), (2t+ 2,2t−1,2t+ 1),(2t−1,2t+ 2,2t+ 1)}.
kk
h?2 +Q``2bTQM/BM; ;2M2`iQ` Ki`Bt G Q7 (S01, S10, S11) BM
{(2t,2t,2t+ 2),(2t+ 2,2t,2t),(2t,2t+ 2,2t),(2t−2,2t+ 2,2t+ 2), (2t+ 2,2t−2,2t+ 2),(2t+ 2,2t+ 2,2t−2)}
?b i?2 T`QT2`iv i?i rank(GGT) = 0 r?B+? BKTHB2b i?i dim(Hull(C)) = 2 ̸= 1 #v S`QTQbBiBQM kXkX9X h?2 +Q``2bTQM/BM; ;2M2`iQ` Ki`Bt G Q7 (S01, S10, S11) BM
{(2t+ 1,2t−1,2t+ 2),(2t+ 2,2t+ 1,2t−1),(2t+ 1,2t+ 2,2t−1), (2t−1,2t+ 1,2t+ 2),(2t+ 2,2t−1,2t+ 1),(2t−1,2t+ 2,2t+ 1)}
?b i?2 T`QT2`iv i?i rank(GGT) = 2 r?B+? BKTHB2b i?i dim(Hull(C)) = 0 ̸= 1 #v S`QTQbBiBQM kXkX9X
*b2 RXjX n ≡ 4(mod 6)X h?2M n = 6t+ 4 7Q` bQK2 TQbBiBp2 BMi2;2` tX h?2 i`BTH2b (S01, S10, S11)biBb7vBM;S01+S10+S11=n= 6t+4M/min{S10+S11, S01+S11, S10+ S01}=12n
3
2−1 = 4t+ 1 `2 BM i?2 b2i
{(2t,2t+ 1,2t+ 3),(2t−1,2t+ 2,2t+ 3),(2t+ 3,2t−1,2t+ 2), (2t+ 3,2t+ 2,2t−1),(2t−1,2t+ 3,2t+ 2),(2t+ 2,2t+ 3,2t−1), (2t+ 2,2t−1,2t+ 3),(2t−1,2t+ 2,2t+ 3),(2t+ 3,2t−1,2t+ 2), (2t+ 3,2t+ 2,2t−1),(2t−1,2t+ 3,2t+ 2),(2t+ 2,2t+ 3,2t−1), (2t+ 3,2t+ 3,2t−2),(2t−2,2t+ 3,2t+ 3),(2t−2,2t+ 3,2t+ 3)}.
h?2 +Q``2bTQM/BM; ;2M2`iQ` Ki`B+2b G ?p2 i?2 T`QT2`iv i?i rank(GGT) = 2 r?B+? BKTHB2b i?i dim(Hull(C)) = 0̸= 1 #v S`QTQbBiBQM kXkX9X
*b2 kX n−1 =S01+S10+S11X h?2 2tBbi2M+2 Q7 M [n,2,12n
3
2−1]2 +Q/2 rBi? ?mHH /BK2MbBQM QM2 Bb ;Bp2M b 7QHHQrbX
*b2 kXRX n ≡ 0(mod 6)X h?2M n−1 ≡5(mod 6)X "v h?2Q`2K jX9XR- i?2`2 2tBbib M [n−1,2,/
2(n−1) 3
0]2 +Q/2 rBi? ;2M2`iQ` Ki`Bt G M/ ?mHH /BK2MbBQM QM2X G2i G′ = [0 G]X Ai Bb MQi /B{+mHi iQ b22 i?i G′ ;2M2`i2b M [n,2,/
2(n−1) 3
0]2 +Q/2DrBi?
?mHH /BK2MbBQM QM2X aBM+2 /
2(n−1) 3
0=12n
3
2−1- D ?b T`K2i2`b [n,2,12n
3
2−1]2X
kj
*b2 kXkX n ≡ 2(mod 6)X h?2M n−1 ≡1(mod 6)X "v h?2Q`2K jXkXR- i?2`2 2tBbib M M[n−1,2,/
2(n−1) 3
0]2 +Q/2 rBi? ;2M2`iQ` Ki`Bt GM/ ?mHH /BK2MbBQM QM2X G2i G′ = [0 G]X Ai Bb MQi /B{+mHi iQ b22 i?i G′ ;2M2`i2b M [n,2,/
2(n−1) 3
0
]2 +Q/2DrBi?
?mHH /BK2MbBQM QM2X aBM+2 /
2(n−1) 3
0=12n
3
2−1- D ?b T`K2i2`b [n,2,12n
3
2−1]2X
*b2 kXjX n ≡ 4(mod 6)X h?2M n−1 ≡3(mod 6)X "v h?2Q`2K jXjXR- i?2`2 2tBbib M M [n−1,2,/
2(n−1) 3
0−1]2 +Q/2 rBi? ;2M2`iQ` Ki`Bt GM/ ?mHH /BK2MbBQM QM2X G2i G′ = [0G]X Ai Bb MQi /B{+mHi iQ b22 i?i G′ ;2M2`i2b M [n,2,/
2(n−1) 3
0−1]2
+Q/2 D rBi? ?mHH /BK2MbBQM QM2X aBM+2 /
2(n−1) 3
0−1 = 12n
3
2−1- D ?b T`K2i2`b [n,2,12n
3
2−1]2X
h?2 2MmK2`iBQM 7Q` 2+? +b2 7QHHQrb 7`QK h?2Q`2K jX9XR- h?2Q`2K jXkXR- M/
h?2Q`2K jXjXR- `2bT2+iBp2HvX
1tKTH2 jX8XjX "v 1tKTH2 jX9Xk- r2 ?p2 i?iC Bb HBM2` +Q/2 rBi? T`K2i2`b [17,2,8]2 ;2M2`i2/ #v
G=
⎡
⎣0 0 0 0 0 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 1 1 1 1 1
⎤
⎦.
G2i G′ = [0 G]X "v h?2Q`2K jX8Xk- r2 ?p2 i?i G′ ;2M2`i2b M QTiBKH [18,2,7]2
+Q/2 rBi? ?mHH /BK2MbBQM QM2X
1tKTH2 jX8X9X "v 1tKTH2 jXkXk- r2 ?p2 i?iC Bb HBM2` +Q/2 rBi? T`K2i2`b [13,2,8]2 ;2M2`i2/ #v
G=
⎡
⎣0 0 0 0 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 0 0 1 1 1 1 1
⎤
⎦.
G2i G′ = [0 G]X "v h?2Q`2K jX8Xk- r2 ?p2 i?i G′ ;2M2`i2b M QTiBKH [14,2,7]2
+Q/2 rBi? ?mHH /BK2MbBQM QM2X
1tKTH2 jX8X8X "v 1tKTH2 jXjXk- r2 ?p2 i?iC1 Bb HBM2` +Q/2 rBi? T`K2i2`b [15,2,9]2 ;2M2`i2/ #v
G1 =
⎡
⎣0 0 0 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 1 1 1 1 1
⎤
⎦.
k9
G2iG′1 = [0 G1]X "v h?2Q`2K jX8Xk- r2 ?p2 i?i G′1 ;2M2`i2b M QTiBKH[16,2,8]2
+Q/2 rBi? ?mHH /BK2MbBQM QM2X
1tKTH2 jX8XeX "v 1tKTH2 jXjXk- r2 ?p2 i?iC2 Bb HBM2` +Q/2 rBi? T`K2i2`b [15,2,9]2 ;2M2`i2/ #v
G2 =
⎡
⎣0 0 0 0 0 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 1 1 1
⎤
⎦.
G2iG′2 = [0 G2]X "v h?2Q`2K jX8Xk- r2 ?p2 i?i G′2 ;2M2`i2b M QTiBKH[16,2,8]2
+Q/2 rBi? ?mHH /BK2MbBQM QM2X "v h?2Q`2K jX8Xk- r2 ?p2 i?i G′1 M/ G′2 ;2M2`i2 irQ BM2[mBpH2Mi +Q/2bX
h?2 #Qp2 `2bmHib +M #2 bmKK`Bx2/ b 7QHHQrbX h?2Q`2K jX8XdX G2i n ≥3 #2 M BMi2;2`X h?2M
D2(n,2,1) =
⎧⎪
⎪⎨
⎪⎪
⎩ 12n
3
2 B7 n ≡1,5 (mod 6), 12n
3
2−1 B7 n ≡0,2,3,4 (mod 6).
k8
*?Ti2` 9
PTiBKH h2`M`v GBM2` *Q/2b rBi? 1m+HB/2M >mHH .BK2MbBQM PM2
AM i?Bb +?Ti2`- r2 7Q+mb QM +QMbi`m+iBQMb Q7 [n,2]3 +Q/2b rBi? ?mHH /BK2MbBQM QM2X 6Q` 2+? BMi2;2`n ≥3- M QTiBKH[n,2]3+Q/2 rBi? ?mHH /BK2MbBQM QM2 Bb +QMbi`m+i2/X
*QMb2[m2MiHv- i?2 2t+i pHm2 Q7 D3(n,2,1)Bb T`2b2Mi2/ 7Q` HH BMi2;2`b n≥3X
9XR "bB+ *QM+2Tib
6`QK i?2 b2imT BM am#b2+iBQM kXj Q` BM (RN)- HBM2` [n,2]3 +Q/2 C rBi? ;2M2`iQ`
Ki`Bt
G=
⎡
⎣α1
α2
⎤
⎦ U9XRV
+M #2 pB2r2/ Q7 i?2 7Q`K C={0,α1,α2,2α1,2α2,α1+α2,2α1+α2,α1+ 2α2,2α1+ 2α2}. 6`QK UkXjV- r2 ?p2 α1 = %
a11 a12 · · · a1n
&
M/ α2 = %
a21 a22 · · · a2n
&
ke
M/ Bi Bb MQi /B{+mHi iQ b22 i?i ri(α1) = ri(2α1) =
*2 i=1
*2 j=0
Sij, U9XkV
ri(α2) = ri(2α2) =
*2 i=0
*2 j=1
Sij, U9XjV
ri(α1+α2) =ri(2α1+ 2α2) =S01+S02+S10+S11+S20+S22, U9X9V ri(2α1+α2) = ri(α1+ 2α2) =S01+S02+S10+S12+S20+S21. U9X8V
>2M+2-
wtH(C) = min{ri(α1),ri(2α1),ri(α2),ri(2α2),ri(α1+α2), ri(2α1+ 2α2),ri(2α1+α2),ri(α1+ 2α2)}
= min{
*2 i=1
*2 j=0
Sij,
*2 i=0
*2 j=1
Sij, S01+S02+S10+S11+S20+S22,
S01+S02+S10+S12+S20+S21}. U9XeV 6`QK U9XRV- r2 ?p2
GGT =
⎡
⎢⎢
⎣ '2 i=1
'2 j=0
Sij
'2 i=1
'2 j=1
ijSij
'2 i=1
'2 j=1
ijSij
'2 i=0
'2 j=1
Sij
⎤
⎥⎥
⎦(mod 3). U9XdV
1tKTH2 9XRXRX G2i C #2 i?2 i2`M`v HBM2` +Q/2 Q7 H2M;i? 5rBi? ;2M2`iQ` Ki`Bt G=
⎡
⎣1 0 1 0 2 0 1 1 2 1
⎤
⎦
h?2M S10 = S01 = S11 = S02 = S21 = 1 M/ S00 = S20 = S12 = S22 = 0. AM F3, Bi 7QHHQrb i?i
'2 i=1
'2 j=0
Sij = 0,'2
i=1
'2 j=1
ijSij = 0,'2
i=1
'2 j=1
ijSij = 0 M/ '2
i=0
'2 j=1
Sij = 1.
"v U9XdV- Bi 7QHHQrb i?i
G=
⎡
⎣0 0 0 1
⎤
⎦
r?B+? BKTHB2b i?i rank(GGT) = 1 M/ dim(HullH(C)) = 2− rank(GGT) = 1 #v S`QTQbBiBQM kXkX9X
kd
6`QK G2KK kXjX9- Bi +M #2 +QM+Hm/2/ i?i D3(n,2,1)≤
-3n 4
.
. U9X3V
lbBM; i?2 MQiiBQMb #Qp2- i?2 2t+i pHm2 7Q` D3(n,2,1) +M #2 /2`Bp2/ BM i?2 7QHHQrBM; b2+iBQMbX
9Xk n ≡ 1 (mod 4)
AM i?2 7QHHQrBM; i?2Q`2K- r2 ;Bp2 +QMbi`m+iBQMb Q7 M QTiBKH[n,2,13n
4
2]3+Q/2 rBi?
/BK2bBQM 2 M/ 1m+HB/2M ?mHH /BK2MbBQM QM2 Bb ;Bp2M 7Q` HH H2M;i?bn ≡1 (mod 4)X h?2Q`2K 9XkXRX G2i n ≥3 #2 M BMi2;2`X A7 n ≡1 (mod 4)- i?2M
D3(n,2,1) = -3n
4 .
.
S`QQ7X bbmK2 i?i n ≡1 (mod 4)X h?2M n = 4t+ 1 7Q` bQK2 TQbBiBp2 BMi2;2` t M/
13n
4
2 =/
3(4t+1) 4
0= 3tX
6`QK UjX9V- Bi bm{+2b iQ b?Qr i?2 2tBbi2M+2 Q7 M [n,2,3t]3 +Q/2 rBi? ?mHH /BK2M@
bBQM QM2X
*b2 RX t Bb 2p2MX G2i C #2 HBM2` +Q/2 rBi? ;2M2`iQ` Ki`Bt G Q7 i?2 7Q`K U9XRV /2i2`KBM2/ #v
S00 = 0, S01=S10 =S02 =S20 =S12 =S11=S22= t
2, M/ S21= t 2+ 1.
h?2M C Bb M [n,2, d]3 +Q/2- r?2`2
d= min{
*2 i=1
*2 j=0
Sij,
*2 i=0
*2 j=1
Sij, S01+S02+S10+S11+S20+S22,
S01+S02+S10+S12+S20+S21}
= min{3t+ 1,3t+ 1,3t,3t+ 1} #v U9XeV
= 3t.
k3
6`QK U9XdV- r2 ?p2
GGT =
⎡
⎣1 2 2 1
⎤
⎦
r?B+? BKTHB2b i?i rank(GGT) = 1X b /2bB`2/- r2 ?p2 dim(Hull(C)) = 1 #v S`QTQbBiBQM kXkX9X
*b2 kX t Bb Q//X G2i C #2 HBM2` +Q/2 rBi? ;2M2`iQ` Ki`Bt G Q7 i?2 7Q`K U9XRV /2i2`KBM2/ #v
S00 = 0, S02=S20=S12=S21 =S11 = t+ 1
2 M/ S01 =S10=S22= t−1 2 . h?2M C Bb M [n,2, d]3 +Q/2- r?2`2
d= min{
*2 i=1
*2 j=0
Sij,
*2 i=0
*2 j=1
Sij, S01+S02+S10+S11+S20+S22,
S01+S02+S10+S12+S20+S21}
= min{3t+ 1,3t+ 1,3t,3t+ 1} #v U9XeV
= 3t.
6`QK U9XdV- r2 ?p2
GGT =
⎡
⎣1 2 2 1
⎤
⎦
r?B+? BKTHB2b i?irank(GGT) = 1X "v S`QTQbBiBQM kXkX9- r2 i?2`27Q` ?p2dim(Hull(C)) = 1 b /2bB`2/X
1tKTH2 9XkXkX G2i t = 2X "v h?2Q`2K 9XkXR M/ t Bb 2p2M- r2 ?p2 i?i S00 = 0, S01 =S10 = S02 =S20 =S12 =S11 =S22 = 1 M/ S21 = 2X G2i C #2 i?2 i2`M`v HBM2` +Q/2 Q7 H2M;i? 9 rBi? ;2M2`iQ` Ki`Bt
G=
⎡
⎣1 0 0 2 1 1 2 2 2 0 1 2 0 2 1 2 1 1
⎤
⎦.
AM F3, r2 ?p2
kN
'2 i=1
'2 j=0
Sij = 1, '2 i=1
'2 j=1
ijSij = 2, '2 i=1
'2 j=1
ijSij = 2 M/ '2
i=0
'2 j=1
Sij = 1.
"v U9XdV- Bi 7QHHQrb i?i
G=
⎡
⎣1 2 2 1
⎤
⎦
r?B+? BKTHB2b i?i rank(GGT) = 1 M/ dim(Hull(C)) = 2− rank(GGT) = 1 #v S`QTQbBiBQM kXkX9X h?2M C Bb M QTiBKH [9,2,6]3 +Q/2 rBi? ?mHH /BK2MbBQM QM2 #v U9X3VX
9Xj n ≡ 2 (mod 4)
AM i?2 7QHHQrBM; i?2Q`2K- r2 ;Bp2 +QMbi`m+iBQMb Q7 QTiBKH [n,2,13n
4
2]3 +Q/2b Q7 bm+? H2M;i?b rBi? ?mHH /BK2MbBQM QM2 r?2`2 n≡2 (mod 4)X
h?2Q`2K 9XjXRX G2i n ≥3 #2 M BMi2;2`X A7 n ≡2 (mod 4)- i?2M D3(n,2,1) =
-3n 4
. .
S`QQ7X bbmK2 i?i n ≡2 (mod 4)X h?2M n = 4t+ 2 7Q` bQK2 TQbBiBp2 BMi2;2` t M/
13n
4
2 =/
3(4t+2) 4
0= 3t+ 1X
6`QK i?2 #QmM/ BM U9X3V- Bi bm{+2b iQ b?Qr i?2 2tBbi2M+2 Q7 M [n,2,3t+ 1]3 +Q/2 rBi? ?mHH /BK2MbBQM QM2X
*b2 RX t Bb 2p2MX G2i C #2 HBM2` +Q/2 rBi? ;2M2`iQ` Ki`Bt G Q7 i?2 7Q`K U9XRV /2i2`KBM2/ #v
S00= 0, S01 =S10=S11= t
2+ 1, S02 =S20 =S21=S22= t
2 M/ S12 = t 2 −1.
h?2M C Bb M [n,2, d]3 +Q/2- r?2`2 d= min{
*2 i=1
*2 j=0
Sij,
*2 i=0
*2 j=1
Sij, S01+S02+S10+S11+S20+S22,
S01+S02+S10+S12+S20+S21}
= min{3t+ 1,3t+ 1,3t+ 3,3t+ 1} #v U9XeV
= 3t+ 1.
jy