OFFSET
0,15
LINKS
Robert Israel, Table of n, a(n) for n = 0..10000
FORMULA
a(n) = -(1/n)*Sum_{k=1..n} A050449(k)*a(n-k), a(0) = 1.
O.g.f.: Sum_{n >= 0} (-1)^n*x^(n*(2*n-1)) / Product_{k = 1..n} ( 1 - x^(4*k) ). Cf. A284316. - Peter Bala, Nov 28 2020
MAPLE
V:= Vector(100):
V[1]:= 1:
for k from 0 to 24 do
V[4*k+2..100]:= V[4*k+2..100] - V[1..99-4*k]
od:
convert(V, list); # Robert Israel, May 03 2017
MATHEMATICA
CoefficientList[Series[Product[1 - x^(4k + 1), {k, 0, 100}], {x, 0, 100}], x] (* Indranil Ghosh, Mar 25 2017 *)
PROG
(PARI) Vec(prod(k=0, 100, 1 - x^(4*k + 1)) + O(x^101)) \\ Indranil Ghosh, Mar 25 2017
CROSSREFS
KEYWORD
sign,easy
AUTHOR
Seiichi Manyama, Mar 24 2017
STATUS
approved