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A366102
Expansion of (1/x) * Series_Reversion( x*(1+x+x^4)/(1+x) ).
2
1, 0, 0, 0, -1, 1, -1, 1, 4, -10, 17, -25, -1, 76, -217, 443, -490, -94, 1999, -6208, 11527, -12350, -4471, 63826, -184055, 332713, -342399, -231390, 2101215, -5790892, 10230983, -9625472, -10237792, 71714387, -190381165, 324440310, -275119412, -430340403
OFFSET
0,9
FORMULA
a(n) = (1/(n+1)) * Sum_{k=0..floor(n/4)} (-1)^(n-k) * binomial(n+k,k) * binomial(n-3*k-1,n-4*k).
PROG
(PARI) a(n) = sum(k=0, n\4, (-1)^(n-k)*binomial(n+k, k)*binomial(n-3*k-1, n-4*k))/(n+1);
CROSSREFS
Sequence in context: A310541 A246394 A310542 * A183905 A301288 A347154
KEYWORD
sign
AUTHOR
Seiichi Manyama, Sep 29 2023
STATUS
approved