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%I #7 Oct 13 2015 10:11:33
%S 1,2,9,88,1425,32886,992446,37106784,1657248417,86128357150,
%T 5107663394691,340427678198400,25194445531808735,2050156960934135340,
%U 181938723871328671500,17487609556155439051136,1809886850192627028383553,200670984392566362698014110,23730570474434159458296269953
%N a(n) = binomial(n^2+n+1,n) * (n+1) / (n^2+n+1) for n>=0.
%F a(n) = (n+1)*A135862(n).
%e G.f.: A(x) = 1 + 2*x + 9*x^2 + 88*x^3 + 1425*x^4 + 32886*x^5 +...
%t Table[(Binomial[n^2+n+1,n](n+1))/(n^2+n+1),{n,0,20}] (* _Harvey P. Dale_, Oct 13 2015 *)
%o (PARI) {a(n)=binomial(n^2+n+1,n)*(n+1)/(n^2+n+1)}
%o for(n=0,20,print1(a(n),", "))
%Y Cf. A135862, A135860.
%K nonn
%O 0,2
%A _Paul D. Hanna_, Aug 23 2013