OFFSET
0,4
COMMENTS
First column of A182826.
FORMULA
D-finite with recurrence: a(n) +(2n-1)*a(n-1) +4*(n-1)^2*a(n-2)=0. - R. J. Mathar, Nov 17 2011
MATHEMATICA
Table[(-1)^n*2^n*n!*LegendreP[n, 1/2], {n, 0, 20}] (* Vaclav Kotesovec, May 06 2017 *)
PROG
(PARI) x='x+O('x^55); Vec(serlaplace(1/sqrt(1+2*x+4*x^2)))
CROSSREFS
KEYWORD
sign,easy
AUTHOR
Paul Barry, Dec 05 2010
STATUS
approved