OFFSET
0,2
LINKS
Paul D. Hanna, Table of n, a(n) for n = 0..1024
EXAMPLE
G.f.: A(x) = 1 + 2*x + 8*x^2 + 36*x^3 + 166*x^4 + 770*x^5 + 3574*x^6 + 16560*x^7 + 76516*x^8 + 352498*x^9 + 1619014*x^10 + 7414134*x^11 + 33855996*x^12 +...
where
A(x)^2 = 1 + 4*x + 20*x^2 + 104*x^3 + 540*x^4 + 2780*x^5 + 14180*x^6 + 71688*x^7 + 359452*x^8 + 1788988*x^9 + 8844064*x^10 +...+ A274965(2*n+1)*x^n +...
PROG
(PARI) {a(n) = my(A, B=1); for(k=0, 2*n, B = B^2 + x^(2*n+1-k) +O(x^(2*n+2))); A = sqrt( (B - subst(B, x, -x))/(2*x) ); polcoeff(A, 2*n)}
for(n=0, 30, print1(a(n), ", "))
CROSSREFS
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Aug 14 2016
STATUS
approved