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A104085 Coefficient list length of Poincaré-like polynomials made from A047845, indices of odd nonprimes (group dimension equivalent plus one). 0
1, 2, 11, 26, 47, 72, 99, 132, 167, 206, 251, 300, 351, 406, 463, 526, 591, 660, 735, 812, 893, 978, 1065, 1156, 1249, 1344, 1443 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

There is a possibility that these polynomials also represent groups?

LINKS

Table of n, a(n) for n=1..27.

FORMULA

P(m)=Product[1 + t^(2*A047845(n) + 1), {n, 1, m}] a(n) =Length[CoefficientList[P(n),x]]

MATHEMATICA

(* Make A047845*) a = Flatten[Table[If[PrimeQ[2*n + 1] == False, n, {}], {n, 0, 50}]]; (* find lengths of polynomials*) Table[Length[CoefficientList[Product[1 + t^(2*a[[n]] + 1), {n, 1, m}], t]], { m, 0, Length[a]}]

CROSSREFS

Cf. A047845.

Sequence in context: A296285 A077482 A141428 * A080663 A248118 A320648

Adjacent sequences:  A104082 A104083 A104084 * A104086 A104087 A104088

KEYWORD

nonn,uned

AUTHOR

Roger L. Bagula, May 16 2007

STATUS

approved

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Last modified February 24 01:16 EST 2020. Contains 332195 sequences. (Running on oeis4.)