A139379 - OEIS

%I #8 Sep 24 2021 09:06:31

%S 0,1,2,6,15,41,113,327,982,3066,9892,32820,111390,385042,1350722,

%T 4795246,17191535,62139697,226167557,828085651,3047683955,11267975677,

%U 41829610607,155848125601,582566960465,2184167358991,8211247681373

%N A Jacobsthal Catalan convolution.

%C Second column of A139377. Row sums of A139377 give a(n+1).

%F G.f.: xc(x)/(1-x-2x^2), c(x) the g.f. of A000108; a(n)=sum{k=0..n, A000108(k)*A001045(n-k)};

%F D-finite with recurrence n*a(n) +(6-5*n)*a(n-1) +2*(n-3)*a(n-2) +4*(2*n-3)*a(n-3)=0. - _R. J. Mathar_, Oct 25 2012

%K easy,nonn

%O 0,3

%A _Paul Barry_, Apr 15 2008