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A373014
Number of partitions p of n such that max(p) == 1 mod 3.
1
0, 1, 1, 1, 2, 2, 3, 5, 7, 9, 14, 18, 25, 34, 45, 58, 78, 99, 128, 165, 210, 264, 336, 419, 525, 655, 813, 1003, 1242, 1522, 1867, 2283, 2783, 3379, 4105, 4960, 5989, 7214, 8670, 10391, 12447, 14858, 17719, 21088, 25055, 29705, 35187, 41581, 49084, 57844, 68072, 79974
OFFSET
0,5
FORMULA
G.f.: Sum_{k>=0} x^(3*k+1) / Product_{j=1..3*k+1} (1-x^j).
A000041(n) = A363045(n) + a(n) + A373015(n).
EXAMPLE
a(7) = 5 counts these partitions: 7, 43, 421, 4111, 1111111.
PROG
(PARI) my(N=60, x='x+O('x^N)); concat(0, Vec(sum(k=0, N, x^(3*k+1)/prod(j=1, 3*k+1, 1-x^j))))
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, May 20 2024
STATUS
approved