A356962 - OEIS

%I #10 Sep 06 2022 14:05:45

%S 1,0,0,3,6,10,465,3801,20608,461196,7609185,85446955,1661943756,

%T 38070386718,692342989429,15023805426735,404978989779120,

%U 10131679290423736,264474729910772433,8059571860456028835,249785940327179846500,7837578968934515202570

%N E.g.f. satisfies log(A(x)) = x^2/2 * (exp(x*A(x)) - 1) * A(x).

%F a(n) = n! * Sum_{k=0..floor(n/3)} (n-k+1)^(k-1) * Stirling2(n-2*k,k)/(2^k * (n-2*k)!).

%o (PARI) a(n) = n!*sum(k=0, n\3, (n-k+1)^(k-1)*stirling(n-2*k, k, 2)/(2^k*(n-2*k)!));

%Y Cf. A349557, A356785, A356963.

%Y Cf. A356951, A356967.

%K nonn

%O 0,4

%A _Seiichi Manyama_, Sep 06 2022