cp's OEIS Frontend

A202087 Number of partitions of 5n such that cn(0,5) <= cn(1,5) = cn(4,5) = cn(2,5) = cn(3,5).

%I A202087 #10 Sep 16 2019 21:10:11
%S A202087 1,0,1,5,16,40,91,191,391,776,1521,2921,5537,10301,18888,34061,60568,
%T A202087 106162,183778,314258,531573,889779,1475249,2423709,3948471,6380559,
%U A202087 10232772,16291635,25759898,40462162,63156523,97984149,151139494
%N A202087 Number of partitions of 5n such that cn(0,5) <= cn(1,5) = cn(4,5) = cn(2,5) = cn(3,5).
%C A202087 For a given partition, cn(i,n) means the number of its parts equal to i modulo n.
%H A202087 Andrew Howroyd, <a href="/A202087/b202087.txt">Table of n, a(n) for n = 0..999</a>
%H A202087 <a href="/wiki/Partitions_of_5n">Index and properties of sequences related to partitions of 5n</a>
%F A202087 a(n) = A036880(n) - A036883(n).
%F A202087 a(n) = A046776(n) + A202088(n).
%F A202087 G.f.: Sum_{k>=0} x^(2*k)/(Product_{j=1..k} 1 - x^j)^5. - _Andrew Howroyd_, Sep 16 2019
%o A202087 (PARI) seq(n)={Vec(sum(k=0, n\2, x^(2*k)/prod(j=1, k, 1 - x^j + O(x*x^n))^5) + O(x*x^n), -(n+1))} \\ _Andrew Howroyd_, Sep 16 2019
%Y A202087 Cf. A036880, A036883, A046776, A202088.
%K A202087 nonn
%O A202087 0,4
%A A202087 _Max Alekseyev_, Dec 11 2011
%E A202087 a(0)=1 prepended by _Andrew Howroyd_, Sep 16 2019