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%I #9 Mar 13 2023 16:10:19
%S 1,0,0,1,-1,2,-5,21,-109,671,-4772,38591,-350036,3520830,-38903271,
%T 468490350,-6107642906,85704534787,-1288021805215,20641247413120,
%U -351374756822383,6332030169529731,-120427840368046909,2410627702030000447,-50661193580285096086
%N a(n) = Sum_{k=0..floor(n/3)} Stirling1(n - 2*k,k).
%F G.f.: Sum_{k>=0} (-x)^k * Product_{j=0..k-1} (j - x^2).
%p A357919 := proc(n)
%p add(stirling1(n-2*k,k),k=0..n/3) ;
%p end proc:
%p seq(A357919(n),n=0..70) ; # _R. J. Mathar_, Mar 13 2023
%o (PARI) a(n) = sum(k=0, n\3, stirling(n-2*k, k, 1));
%o (PARI) my(N=30, x='x+O('x^N)); Vec(sum(k=0, N, (-x)^k*prod(j=0, k-1, j-x^2)))
%Y Cf. A357901, A357920.
%K sign
%O 0,6
%A _Seiichi Manyama_, Oct 20 2022
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