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A363075
Number of partitions of n such that 3*(least part) + 1 = greatest part.
3
0, 0, 0, 0, 1, 1, 2, 3, 6, 6, 10, 12, 18, 20, 27, 32, 42, 47, 59, 67, 85, 94, 113, 126, 152, 169, 198, 220, 257, 282, 326, 359, 413, 452, 512, 563, 639, 695, 781, 853, 958, 1041, 1161, 1261, 1402, 1524, 1685, 1827, 2021, 2186, 2407, 2604, 2861, 3088, 3385, 3657, 4002, 4316, 4704, 5069, 5531
OFFSET
1,7
FORMULA
G.f.: Sum_{k>=1} x^(4*k+1)/Product_{j=k..3*k+1} (1-x^j).
PROG
(PARI) my(N=70, x='x+O('x^N)); concat([0, 0, 0, 0], Vec(sum(k=1, N, x^(4*k+1)/prod(j=k, 3*k+1, 1-x^j))))
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, May 17 2023
STATUS
approved