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A365758
G.f. satisfies A(x) = 1 + x*A(x) / (1 - x^4*A(x)^5).
1
1, 1, 1, 1, 1, 2, 8, 29, 85, 212, 481, 1081, 2627, 7100, 20328, 58023, 160430, 430391, 1140892, 3051678, 8334638, 23199896, 65148939, 182781853, 510225082, 1419091293, 3948954920, 11034704856, 31001204632, 87466532564, 247303929326, 699572256145
OFFSET
0,6
FORMULA
a(n) = Sum_{k=0..floor(n/4)} binomial(n-3*k-1,k) * binomial(n+k+1,n-4*k) / (n+k+1).
PROG
(PARI) a(n) = sum(k=0, n\4, binomial(n-3*k-1, k)*binomial(n+k+1, n-4*k)/(n+k+1));
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Sep 18 2023
STATUS
approved