A144577 Numerators of expansion of exp(1-sqrt(1-x-2*x^2)).

1, 1, 5, 55, 757, 4973, 194671, 842411, 11218933, 3358395757, 115106092471, 2189182968473, 7379994323497, 1699615680368861, 19346973713722411, 23008945996332629551, 1335947317588460238301, 8289679255721758160317, 1095056665754286849584771

Offset

0,3

Links

Robert Israel, Table of n, a(n) for n = 0..367

Formula

A144577/A144578 is D-finite with recurrence 64*b(n) + 48*b(n+1) + (32*n^2 + 96*n + 76)*b(n+2) + (24*n^2 + 120*n + 145)*b(n+3) + (-12*n^2 - 66*n - 72)*b(n+4) + (-4*n^2 - 36*n - 80)*b(n+5)=0. - Robert Israel, Feb 07 2019

Example

1 + (1/2)*x + (5/4)*x^2 + (55/48)*x^3 + (757/384)*x^4 + (4973/1920)*x^5 + (...

Maple

S:= series(exp(1-sqrt(1-x-2*x^2), x, 31):
seq(numer(coeff(S, x, n)), n=0..30); # Robert Israel, Feb 07 2019

Crossrefs

Cf. A144578.

Sequence in context: A292805 A112019 A131846 * A234508 A132865 A294051

Adjacent sequences: A144574 A144575 A144576 * A144578 A144579 A144580

Keyword

nonn,frac

Author

N. J. A. Sloane, Jan 07 2009

Status

approved