A258476 - OEIS

%I #4 May 31 2015 10:39:35

%S 1,8,37,129,376,966,2258,4901,10024,19509,36438,65653,114753,195144,

%T 324164,526911,840581,1317461,2033445,3092660,4643571,6885877,

%U 10099775,14655962,21067353,30002794,42376093,59364880,82558632,113985165,156352359,213082865

%N Number of partitions of n into two sorts of parts having exactly 6 parts of the second sort.

%H Alois P. Heinz, <a href="/A258476/b258476.txt">Table of n, a(n) for n = 6..1000</a>

%p b:= proc(n, i) option remember; series(`if`(n=0, 1,

%p       `if`(i<1, 0, add(b(n-i*j, i-1)*add(x^t*

%p        binomial(j, t), t=0..min(6, j)), j=0..n/i))), x, 7)

%p     end:

%p a:= n-> coeff(b(n$2), x, 6):

%p seq(a(n), n=6..40);

%Y Column k=6 of A256193.

%K nonn

%O 6,2

%A _Alois P. Heinz_, May 31 2015