A320595 Number of partitions of n with seven parts in which no part occurs more than twice.

1, 2, 3, 6, 9, 14, 21, 30, 41, 57, 75, 99, 129, 165, 207, 261, 322, 396, 483, 585, 701, 840, 995, 1176, 1382, 1617, 1880, 2183, 2518, 2898, 3322, 3797, 4321, 4911, 5556, 6275, 7066, 7939, 8892, 9947, 11092, 12350, 13719, 15214, 16832, 18601, 20507, 22580

Offset: 16

Author

Alois P. Heinz, Oct 16 2018

Keywords

• nonn
• easy

Links

• Alois P. Heinz, Table of n, a(n) for n = 16..10000

Crossrefs

Column k=7 of A209318.

Formula

G.f.: -(x^12-x^10-x^8-x^7+x^3+x+1)*x^16 / ((x^2-x+1) *(x^4+x^3+x^2+x+1) *(x^6+x^5+x^4+x^3+x^2+x+1) *(x^2+1) *(x^2+x+1)^2 *(x+1)^3 *(x-1)^7).