A107615 Coefficient list length of Poincaré-like polynomials made from A047845, indices of 4*n+1 nonprimes as the m(i) exponents.

1, 2, 7, 18, 31, 48, 71, 96, 125, 158, 193, 232, 273, 316, 363, 416, 475, 536, 599, 664, 731, 802, 875, 952, 1033, 1116, 1201, 1290, 1383, 1478, 1579

Offset

1,2

Links

Table of n, a(n) for n=1..31.

Formula

P(m) = Product[1 + t^(2*A045751(n) + 1), {n, 1, m}] a(n) = Length[CoefficientList[P(n),x]].

Mathematica

a = Flatten[Table[If[PrimeQ[4*n + 1] == False, n, {}], {n, 0, 50}]]; Table[Length[CoefficientList[Product[1 + t^(2*a[[n]] + 1), {n, 1, m}], t]], { m, 0, Length[a]}]

Crossrefs

Cf. A045751.

Sequence in context: A104310 A301325 A001114 * A195605 A184096 A136583

Adjacent sequences: A107612 A107613 A107614 * A107616 A107617 A107618

Keyword

nonn,uned

Author

Roger L. Bagula, May 16 2007

Status

approved