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A143696
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Number of additive cyclic codes over GF(4) of length n that can be generated by one codeword.
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1
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4, 10, 24, 46, 72, 260, 400, 766, 1584, 2900, 4104, 19596, 16392, 67240, 139968, 196606, 266256, 1098760, 1048584, 3416604, 10454400, 10506260, 16810000, 83667116, 75497616, 167854100, 415239264, 1275614776, 1073741832, 6341140000, 6179217664, 12884901886
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OFFSET
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1,1
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REFERENCES
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W. C. Huffman, Additive cyclic codes over F_4, Advances in Math. Communication, 2 (2008), 309-343.
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LINKS
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FORMULA
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PROG
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(PARI) csiz(n, q) = {list = listcreate(n); A = vector(n); for (i=0, n-1, ai = i+1; if (!A[ai], ni = i; nai = ni+1; s = 0; while (! A[nai], A[nai] = 1; s++; ni = lift(Mod(ni*q, n)); nai = ni+1; ); listput(list, s); ); ); return (Vec(list)); } /* algorithm from arXiv:cs/0703129 */
a(n) = {expz = 2^valuation(n, 2); y = n/expz; d = csiz(y, 2); prod(i=1, length(d), 1 + (2^(expz*d[i])-1)*(2^d[i]+1)/(2^d[i]-1)); } \\ Michel Marcus, Mar 06 2013
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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