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%I #27 Sep 08 2022 08:46:06
%S 24,216,2184,24696,310344,4304376,65444424,1083832056,19437971784,
%T 375544415736,7779464328264,172062025581816,4047849158698824,
%U 100946105980181496,2660400563437957704,73890563849015945976,2157336929022064219464,66059202473570840113656,2116993226046938197020744
%N 4-Fubini numbers.
%H Vincenzo Librandi, <a href="/A232474/b232474.txt">Table of n, a(n) for n = 4..200</a>
%H Andrei Z. Broder, <a href="http://dx.doi.org/10.1016/0012-365X(84)90161-4">The r-Stirling numbers</a>, Discrete Math. 49, 241-259 (1984).
%H I. Mezo, <a href="http://arxiv.org/abs/1308.1637">Periodicity of the last digits of some combinatorial sequences</a>, arXiv preprint arXiv:1308.1637 [math.CO], 2013.
%F From _Peter Bala_, Dec 16 2020: (Start)
%F a(n+4) = Sum_{k = 0..n} (k+4)!/k!*( Sum{i = 0..k} (-1)^(k-i)*binomial(k,i)*(i+4)^n ).
%F a(n+4) = Sum_{k = 0..n} 4^(n-k)*binomial(n,k)*( Sum_{i = 0..k} Stirling2(k,i)*(i+4)! ).
%F E.g.f. with offset 0: 24*exp(4*z)/(2 - exp(z))^5 = 24 + 216*z + 2184*z^2/2! + 24696*z^3/3! + .... (End)
%F a(n) ~ n! / (2 * log(2)^(n+1)). - _Vaclav Kotesovec_, Dec 17 2020
%p # r-Stirling numbers of second kind (e.g. A008277, A143494, A143495):
%p T := (n,k,r) -> (1/(k-r)!)*add ((-1)^(k+i+r)*binomial(k-r,i)*(i+r)^(n-r),i = 0..k-r):
%p # r-Bell numbers (e.g. A000110, A005493, A005494):
%p B := (n,r) -> add(T(n,k,r),k=r..n);
%p SB := r -> [seq(B(n,r),n=r..30)];
%p SB(2);
%p # r-Fubini numbers (e.g. A000670, A232472, A232473, A232474):
%p F := (n,r) -> add((k)!*T(n,k,r),k=r..n);
%p SF := r -> [seq(F(n,r),n=r..30)];
%p SF(4);
%t Fubini[n_, r_] := Sum[k!*Sum[(-1)^(i+k+r)*(i+r)^(n-r)/(i!*(k-i-r)!), {i, 0, k-r}], {k, r, n}]; Table[Fubini[n, 4], {n, 4, 22}] (* _Jean-François Alcover_, Mar 30 2016 *)
%o (Magma) r:=4; r_Fubini:=func<n,r | &+[Factorial(k)*&+[(-1)^(k+h+r)*(h+r)^(n-r)/(Factorial(h)*Factorial(k-h-r)): h in [0..k-r]]: k in [r..n]]>;
%o [r_Fubini(n, r): n in [r..22]]; // _Bruno Berselli_, Mar 30 2016
%Y Cf. A008277, A143494, A143495, A000110, A005493, A005494, A000670, A232472, A232473, A232474.
%K nonn,easy
%O 4,1
%A _N. J. A. Sloane_, Nov 27 2013
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