Construction of a linear code [56,17,17] over GF(2): [1]: [56, 17, 17] Linear Code over GF(2) Construction from a stored generator matrix
last modified: 2001-03-12
From Brouwer's table (as of 2007-02-13)Lb(56,17) = 17 MoY
Ub(56,17) = 20 follows by a one-step Griesmer bound from: Ub(35,16) = 10 follows by a one-step Griesmer bound from: Ub(24,15) = 4 otherwise adding a parity check bit would contradict: Ub(25,15) = 5 Si
References MoY: M. Morii & T. Yoshimura, email comm. Nov 1993-Jan 1994. Si: J. Simonis, Binary even [25,15,6] codes do not exist, IEEE Trans. Inform. Theory IT-33 (Jan. 1987) 151-153.
この最良符号の(n、k、d)のパラメータは以下の
表(データベース)で管理されています。
Bounds on the minimum distance of linear codes
http://www.rz.uni-karlsruhe.de/~kg11/codetables/BKLC/BKLC_query.php
60年代には嵩忠雄先生、たとえば
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(127,43,31)符号
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From Brouwer's table (as of 2007-02-13)Lb(125,40) = 32 is found by
shortening of:
Lb(128,43) = 32 is found by adding a parity check bit to:
Lb(127,43) = 31 BCH
Ub(125,40) = 40 is found by considering shortening to:
Ub(112,27) = 40 otherwise adding a parity check bit would contradict:
Ub(113,27) = 41 Bro
References
BCH: T. Kasami & N. Tokura, Some remarks on BCH bounds and minimum
weights of binary primitive BCH codes, IEEE Trans. Inform. Theory IT-15
(May 1969) 408-413.
Or: a BCH code.
Bro: A.E. Brouwer, The linear programming bound for binary linear codes,
IEEE Trans. Inform. Th. 39 (1993) 677-680.
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70年代には、杉山康夫先生, 笠原正雄先生, 平沢茂一先生,
滑川敏彦先生らです。たとえば、
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(156,96,17)符号
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From Brouwer's table (as of 2007-02-13)Lb(156,96) = 17 Su
Ub(156,96) = 26 is found by considering shortening to:
Ub(124,64) = 26 otherwise adding a parity check bit would contradict:
Ub(125,64) = 27 BK
References
BK: Detlef Berntzen & Peter Kemper, email, Feb. 1993.
Su: Y. Sugiyama, M. Kasahara, S. Hirasawa & T. Namekawa, Some efficient
binary codes constructed using Srivastava codes, IEEE Trans. Inform.
Theory IT-21 (Sep. 1975) 581-582. Y. Sugiyama, M. Kasahara, S. Hirasawa
& T. Namekawa, Further results on Goppa codes and their applications to
constructing efficient binary codes, IEEE Trans. Inform. Theory IT-22
(Sep. 1976) 518-526.
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90年代に入ってからは、森井昌克らがいくつかの最良符号
を発見しています。たとえば、
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(241,25,93)符号
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From Brouwer's table (as of 2007-02-13)Lb(241,25) = 93 MYI
Ub(241,25) = 106 follows by a one-step Griesmer bound from:
Ub(134,24) = 53 is found by considering shortening to:
Ub(132,22) = 53 BK
References
BK: Detlef Berntzen & Peter Kemper, email, Feb. 1993.
MYI: M. Morii, T. Yoshimura & Y. Itoh, email comm. Feb-Mar 1995.
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2000年代に入ると、毛利公美先生らが最良符号を数多く
登録しています。たとえば、
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(151,61,31)符号
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From Brouwer's table (as of 2007-02-13)Lb(151,61) = 31 MMT
Ub(151,61) = 42 is found by considering shortening to:
Ub(121,31) = 42 otherwise adding a parity check bit would contradict:
Ub(122,31) = 43 Bro
References
Bro: A.E. Brouwer, The linear programming bound for binary linear codes, IEEE Trans. Inform. Th. 39 (1993) 677-680.
MMT: Hideaki TANAKA, Masami MOHRI, Masakatu MORII, email, comm. Feb 2005.
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です。