On Wed, Feb 11, 2009 at 12:24 PM, Paul D Hanna <pauldhanna at juno.com> wrote: > (1) Sum_{n>=0} [ Sum_{k>=1} (2^k*x)^k/k ]^n / n! > > A155200 = [1, 2, 10, 188, 16774, 6745436, 11466849412, ...]. Paul, You stated A155200 and other similar sequences in OEIS as having integer coefficients. Do you have a proof for that? Thanks, Max