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A366182
G.f. A(x) satisfies A(x) = 1/(1 - x)^3 + x*A(x)^3/(1 - x).
3
1, 4, 19, 128, 1037, 9221, 86847, 851073, 8586951, 88598014, 930473246, 9913648325, 106891041270, 1164153791878, 12788021717902, 141518588447588, 1576271179332762, 17657110535606919, 198792746866201879, 2248222906227731856, 25529220583699163958
OFFSET
0,2
FORMULA
a(n) = Sum_{k=0..n} binomial(n+6*k+2,n-k) * binomial(3*k,k)/(2*k+1).
PROG
(PARI) a(n) = sum(k=0, n, binomial(n+6*k+2, n-k)*binomial(3*k, k)/(2*k+1));
CROSSREFS
Partial sums of A366180.
Sequence in context: A306179 A330515 A330534 * A330494 A352306 A352327
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Oct 03 2023
STATUS
approved