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A151684
Let c(n) = x^(2^n-1)*(1-x^(2^n)), g(n) = 1 + x^(2^n-1) + x^(2^n), h(n) = Product_{i=1..n} g(i); then use g.f. (1+2*x) - Sum_{n>=1} c(n)/h(n).
1
1, 1, 1, 0, -1, 1, 1, -1, 0, 0, -2, 1, 2, 0, 2, -1, -5, -1, 1, 3, 7, 1, -8, -8, -6, 3, 18, 16, 0, -17, -31, -21, 19, 51, 47, 3, -70, -106, -48, 71, 170, 156, -18, -243, -318, -132, 253, 564, 455, -130, -819, -1024, -341, 952, 1849, 1355, -606, -2789, -3199, -727, 3410, 5979, 3932, -2678, -9408, -9926, -1281, 12047
OFFSET
0,11
COMMENTS
This g.f. multiplied by h(k) for k large (cf. A151552) gives the g.f. for (A160573 prefixed by an initial 1).
CROSSREFS
KEYWORD
sign
AUTHOR
N. J. A. Sloane, Jun 01 2009
STATUS
approved