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A363077
Number of partitions of n such that 5*(least part) + 1 = greatest part.
2
0, 0, 0, 0, 0, 0, 1, 1, 2, 3, 5, 7, 12, 14, 21, 27, 37, 46, 63, 75, 97, 119, 149, 178, 222, 260, 317, 373, 447, 520, 620, 713, 839, 965, 1123, 1282, 1488, 1687, 1939, 2196, 2508, 2826, 3220, 3610, 4087, 4578, 5157, 5755, 6472, 7199, 8060, 8953, 9991, 11069, 12330, 13625, 15134, 16708, 18508
OFFSET
1,9
FORMULA
G.f.: Sum_{k>=1} x^(6*k+1)/Product_{j=k..5*k+1} (1-x^j).
PROG
(PARI) my(N=60, x='x+O('x^N)); concat([0, 0, 0, 0, 0, 0], Vec(sum(k=1, N, x^(6*k+1)/prod(j=k, 5*k+1, 1-x^j))))
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, May 17 2023
STATUS
approved