OFFSET
0,2
FORMULA
G.f.: 1/sqrt(1-8*x^2)+(1-sqrt(1-8*x^2))/(2*x).
a(n) = sum{k=0..floor(n/2), 2^(n-k) * A000108(k) * C(k+1, n-k)}.
Conjecture D-finite with recurrence: 11*n*(n+1)*a(n)+4*n*(4*n+1)*a(n-1) +8*(27-11*n^2)*a(n-2) -32*(4*n+9)*(n-3)*a(n-3)=0. - R. J. Mathar, Nov 09 2012
a(n) ~ 2^((3*n + 1)/2) / sqrt(Pi*n) if n is even and a(n) ~ 2^((3*n + 2)/2) / (sqrt(Pi)*n^(3/2)) if n is odd. - Vaclav Kotesovec, Nov 19 2021
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Paul Barry, Feb 23 2005
STATUS
approved