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A202087
Number of partitions of 5n such that cn(0,5) <= cn(1,5) = cn(4,5) = cn(2,5) = cn(3,5).
6
1, 0, 1, 5, 16, 40, 91, 191, 391, 776, 1521, 2921, 5537, 10301, 18888, 34061, 60568, 106162, 183778, 314258, 531573, 889779, 1475249, 2423709, 3948471, 6380559, 10232772, 16291635, 25759898, 40462162, 63156523, 97984149, 151139494
OFFSET
0,4
COMMENTS
For a given partition, cn(i,n) means the number of its parts equal to i modulo n.
FORMULA
a(n) = A036880(n) - A036883(n).
a(n) = A046776(n) + A202088(n).
G.f.: Sum_{k>=0} x^(2*k)/(Product_{j=1..k} 1 - x^j)^5. - Andrew Howroyd, Sep 16 2019
PROG
(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
CROSSREFS
KEYWORD
nonn
AUTHOR
Max Alekseyev, Dec 11 2011
EXTENSIONS
a(0)=1 prepended by Andrew Howroyd, Sep 16 2019
STATUS
approved