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A011745
A binary m-sequence: expansion of reciprocal of x^32 + x^28 + x^27 + x + 1 (mod 2, shifted by 31 initial 0's).
18
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, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0
OFFSET
0,1
COMMENTS
Periodic with period 2^32-1 = 3*5*17*257*65537 = 4294967295. - 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, 31], Mod[CoefficientList[1/(x^32 + x^28 + x^27 + x + 1) + O[x]^50, x], 2]] (* Jean-François Alcover, Feb 23 2018 *)
PROG
(PARI) A011745_vec=concat([1..31]*0, Vec(1/(x^32+x^28+x^27+x+1)+O(x^99))%2)
A=matrix(N=32, N, i, j, if(i>1, i==j+1, setsearch([1, 27, 28, N], j)))*Mod(1, 2);
A011745(n)=lift((A^(n-#A+1))[1, 1]) \\ M. F. Hasler, Feb 17 2018
CROSSREFS
Cf. A011655..A011744 for other binary m-sequences, and A011746..A011751 for similar expansions over GF(2).
Sequence in context: A322438 A304572 A070204 * A011744 A358754 A354996
KEYWORD
nonn,easy
EXTENSIONS
Edited by M. F. Hasler, Feb 17 2018
STATUS
approved