A369190 Expansion of (1/x) * Series_Reversion( x / ((1-x)^2 * (1+x)^4) ).

1, 2, 3, -2, -39, -176, -442, -26, 6222, 36062, 113240, 91632, -1303985, -9362520, -34625652, -50327818, 293446186, 2693939308, 11475384425, 23120716658, -62820989127, -813918935104, -3964894957296, -10002153961552, 10192131001136, 250612187843962

Offset

0,2

Links

Table of n, a(n) for n=0..25.

Index entries for reversions of series

Formula

G.f.: exp( Sum_{k>=1} A368467(k) * x^k/k ).

a(n) = (1/(n+1)) * Sum_{k=0..n} (-1)^k * binomial(2*(n+1),k) * binomial(4*(n+1),n-k).

a(n) = (1/(n+1)) * [x^n] ( (1-x)^2 * (1+x)^4 )^(n+1).

Prog

(PARI) a(n) = sum(k=0, n, (-1)^k * binomial(2*(n+1), k)*binomial(4*(n+1), n-k))/(n+1);

Crossrefs

Cf. A291534, A370107.

Cf. A368467.

Sequence in context: A361531 A332734 A178134 * A291489 A075121 A075108

Adjacent sequences: A369187 A369188 A369189 * A369191 A369192 A369193

Keyword

sign

Author

Seiichi Manyama, Feb 10 2024

Status

approved