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URL: https://oeis.org/A361932

⇱ A361932 - OEIS

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A361932
G.f. A(x) satisfies A(x) = 1 + (x * A(x) / (1 - x))^3.
2
1, 0, 0, 1, 3, 6, 13, 33, 84, 208, 522, 1341, 3476, 9042, 23673, 62426, 165504, 440664, 1178168, 3162357, 8517681, 23013294, 62356329, 169408107, 461366499, 1259311824, 3444497550, 9439766700, 25916832981, 71274793968, 196325540206, 541579442133
OFFSET
0,5
FORMULA
a(n) = Sum_{k=0..floor(n/3)} binomial(n-1,n-3*k) * binomial(3*k,k) / (2*k+1).
PROG
(PARI) a(n) = sum(k=0, n\3, binomial(n-1, n-3*k)*binomial(3*k, k)/(2*k+1));
CROSSREFS
Partial sums give A071879.
Sequence in context: A026538 A358454 A372077 * A201951 A104448 A352864
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Oct 15 2023
STATUS
approved