A063026 Reversion of y - y^2 + y^4 - y^5.

0, 1, 1, 2, 4, 9, 21, 52, 135, 368, 1045, 3068, 9230, 28245, 87414, 272544, 854012, 2685897, 8473107, 26805994, 85045674, 270599945, 863529480, 2763745020, 8870777955, 28550721966, 92128996782, 298004209496, 966085311052

Offset

0,4

Links

Table of n, a(n) for n=0..28.

Index entries for reversions of series

Formula

a(n+1) = (1/(n+1)) * Sum_{k=0..floor(n/3)} (-1)^k * binomial(n+k,n) * binomial(2*n-3*k,n). - Seiichi Manyama, Sep 26 2023

Mathematica

CoefficientList[InverseSeries[Series[y - y^2 + y^4 - y^5, {y, 0, 30}], x], x]

Crossrefs

Cf. A063019.

Sequence in context: A136753 A289666 A084261 * A106219 A198304 A032129

Adjacent sequences: A063023 A063024 A063025 * A063027 A063028 A063029

Keyword

nonn,easy

Author

Olivier Gérard, Jul 05 2001

Status

approved