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%I #10 Jan 30 2019 03:19:24
%S 1,3,39,1239,60039,3870279,311229639,29993362119,3369233266119,
%T 432276047602119,62366420037720519,9994350965362162119,
%U 1761334292457572030919,338557476887113316030919,70488382605888266852030919,15802755831536546966525630919
%N Partial sums of the central Lah numbers (A187535).
%F a(n) = 1 + Sum_{k=0..n} binomial(2k-1,k-1)*(2k)!/k!.
%F (n+2)*a(n+2) - (16n^2 + 49n +3 8)*a(n+1) + 4 *(2n+3)^2*a(n) = 0.
%F Asymptotically a(n) ~ 2^(4n)n^n exp(-n)/sqrt(2n*pi).
%p A187536 := proc(n) add(A187535(i),i=0..n) ; end proc:
%p seq(A187536(n),n=0..10) ; # _R. J. Mathar_, Mar 20 2011
%t Table[1 + Sum[Binomial[2k-1,k-1](2k)!/k!, {k, 1, n}], {n, 0, 20}]
%o (Maxima) makelist(1+sum(binomial(2*k-1,k-1)*(2*k)!/k!,k,1,n),n,0,12);
%Y Cf. A187535, A008297, A111596, A187538 - A187540, A187542 - A187548.
%K nonn,easy
%O 0,2
%A _Emanuele Munarini_, Mar 11 2011