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A303944
Number of partitions of n into at most 1^2 copy of 1, 2^2 copies of 2, 3^2 copies of 3, ... .
1
1, 1, 1, 2, 3, 4, 6, 8, 11, 15, 19, 25, 34, 43, 55, 71, 90, 113, 143, 178, 222, 276, 340, 418, 515, 628, 765, 931, 1128, 1362, 1643, 1974, 2369, 2836, 3385, 4033, 4800, 5694, 6745, 7978, 9418, 11096, 13057, 15334, 17985, 21062, 24626, 28753, 33534, 39045, 45408, 52744, 61187
OFFSET
0,4
FORMULA
G.f.: Product_{k>=1} (1-x^(k*(k^2+1)))/(1-x^k).
EXAMPLE
n | | a(n)
----+--------------------------------+------
1 | 1 | 1
2 | 2 | 1
3 | 3, 2+1 | 2
4 | 4, 3+1, 2+2 | 3
5 | 5, 4+1, 3+2, 2+2+1 | 4
6 | 6, 5+1, 4+2, 3+3, 3+2+1, 2+2+2 | 6
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, May 03 2018
STATUS
approved