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A369512
Expansion of (1/x) * Series_Reversion( x * ((1-x)^3-x)^2 ).
1
1, 8, 106, 1706, 30459, 580138, 11548831, 237408978, 5001034821, 107387829120, 2341915361920, 51727723741200, 1154821390130868, 26016595619565008, 590718564607726952, 13504019611821648448, 310553715057038411358, 7179645587769992602252
OFFSET
0,2
FORMULA
a(n) = (1/(n+1)) * Sum_{k=0..n} binomial(2*n+k+1,k) * binomial(7*n+2*k+5,n-k).
PROG
(PARI) my(N=20, x='x+O('x^N)); Vec(serreverse(x*((1-x)^3-x)^2)/x)
(PARI) a(n) = sum(k=0, n, binomial(2*n+k+1, k)*binomial(7*n+2*k+5, n-k))/(n+1);
CROSSREFS
Cf. A369215.
Sequence in context: A055406 A155632 A129278 * A112701 A099695 A236953
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Jan 25 2024
STATUS
approved