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A011744
A binary m-sequence: expansion of reciprocal of x^31 + x^3 + 1 (mod 2, shifted by 30 initial 0's).
2
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, 1, 0
OFFSET
0,1
COMMENTS
Periodic with period 2^31-1 = 2147483647. - M. F. Hasler, Feb 17 2018
REFERENCES
S. W. Golomb, Shift-Register Sequences, Holden-Day, San Francisco, 1967.
H. D. Lueke, Korrelationssignale, Springer 1992, pp. 43-48.
F. J. MacWilliams and N. J. A. Sloane, The Theory of Error-Correcting Codes, Elsevier/North Holland, 1978, p. 408.
MATHEMATICA
Join[Table[0, 30], Mod[CoefficientList[1/(x^31+x^3+1) + O[x]^52, x], 2]] (* Jean-François Alcover, Feb 23 2018 *)
PROG
(PARI) A011744_vec=concat([1..31]*0, Vec(1/(x^32+x^28+x^27+x+1)+O(x^99))%2)
A=matrix(31, 31, i, j, if(i>1, i==j+1, setsearch([3, 31], j)>0))*Mod(1, 2);
A011744(n)=lift((A^(n-30))[1, 1]) \\ M. F. Hasler, Feb 17 2018
CROSSREFS
Cf. A011655, A011656, ..., A011745 for other binary m-sequences, and A011746..A011751 for similar expansions over GF(2).
Sequence in context: A304572 A070204 A011745 * A358754 A354996 A351539
KEYWORD
nonn,easy
STATUS
approved