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A357941
a(n) = Sum_{k=0..floor(n/4)} Stirling2(k,n - 4*k).
2
1, 0, 0, 0, 0, 1, 0, 0, 0, 1, 1, 0, 0, 1, 3, 1, 0, 1, 7, 6, 1, 1, 15, 25, 10, 2, 31, 90, 65, 16, 64, 301, 350, 141, 148, 967, 1701, 1051, 521, 3053, 7771, 6952, 3157, 9792, 34141, 42527, 23850, 34381, 146500, 246776, 181535, 150513, 623381, 1380556, 1327802, 889022, 2691557, 7530777
OFFSET
0,15
FORMULA
G.f.: Sum_{k>=0} x^(5*k)/Product_{j=1..k} (1 - j * x^4).
PROG
(PARI) a(n) = sum(k=0, n\4, stirling(k, n-4*k, 2));
(PARI) my(N=60, x='x+O('x^N)); Vec(sum(k=0, N, x^(5*k)/prod(j=1, k, 1-j*x^4)))
CROSSREFS
Cf. A357926.
Sequence in context: A151511 A048993 A264431 * A257050 A274494 A274490
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Oct 21 2022
STATUS
approved