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A366178
G.f. A(x) satisfies A(x) = 1/(1 - x) + x*A(x)^3/(1 - x)^3.
2
1, 2, 10, 67, 502, 4045, 34279, 301232, 2720266, 25091431, 235394601, 2239139980, 21546299491, 209361514219, 2051379996574, 20245794958408, 201079938971546, 2008276118393320, 20157131084034349, 203215717750220949, 2056913539436637829
OFFSET
0,2
FORMULA
a(n) = Sum_{k=0..n} binomial(n+4*k,n-k) * binomial(3*k,k)/(2*k+1).
PROG
(PARI) a(n) = sum(k=0, n, binomial(n+4*k, n-k)*binomial(3*k, k)/(2*k+1));
CROSSREFS
Partial sums give A366179.
Sequence in context: A245000 A108397 A325995 * A049036 A208561 A152620
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Oct 03 2023
STATUS
approved