A158269 a(n) = coefficient of x^n in the (2^n)-th iteration of x*C(x) where C(x) is the Catalan function (A000108), for n>=1.

1, 4, 72, 4760, 1196800, 1185344160, 4704904407424, 75251548566631296, 4850542035077717613312, 1257976093502471658023554560, 1310350352604009611135942297681920

Offset

1,2

Links

Table of n, a(n) for n=1..11.

Prog

(PARI) {a(n)=local(G=serreverse(x-x^2+O(x^(n+2)))); for(i=2, n+1, G=subst(G, x, G)); polcoeff(G, n)}

Crossrefs

Cf. A158268, A000108, A158825.

Sequence in context: A012995 A076744 A177392 * A024257 A152653 A344693

Adjacent sequences: A158266 A158267 A158268 * A158270 A158271 A158272

Keyword

nonn

Author

Paul D. Hanna, Mar 28 2009

Status

approved