A257565 Generalized Fubini numbers. Square array read by ascending antidiagonals, A(n,k) = 1 + k*(Sum_{j=1..n-1} C(n,j)*A(j,k)); n>=0 and k>=0.
1, 1, 1, 1, 1, 1, 1, 3, 1, 1, 1, 13, 5, 1, 1, 1, 75, 37, 7, 1, 1, 1, 541, 365, 73, 9, 1, 1, 1, 4683, 4501, 1015, 121, 11, 1, 1, 1, 47293, 66605, 17641, 2169, 181, 13, 1, 1, 1, 545835, 1149877, 367927, 48601, 3971, 253, 15, 1, 1, 1, 7087261, 22687565, 8952553, 1306809, 108901, 6565, 337, 17, 1, 1
Offset: 0
Examples
1, 1, 1, 1, 1, 1, ... A000012 1, 1, 1, 1, 1, 1, ... A000012 1, 3, 5, 7, 9, 11, ... A005408 1, 13, 37, 73, 121, 181, ... A003154 1, 75, 365, 1015, 2169, 3971, ... A193252 1, 541, 4501, 17641, 48601, 108901, ... 1, 4683, 66605, 367927, 1306809, 3583811, ... 1, 47293, 1149877, 8952553, 40994521, 137595781, ... A000012, A000670, A050351, A050352, A050353,
References
- M. Mureşan, On the generalized Fubini numbers. (Romanian) Stud. Cercet. Mat. 37, 70-76 (1985).
Links
- Robert Gill, The number of elements in a generalized partition semilattice, Discrete mathematics 186.1-3 (1998): 125-134. See Example 1.
- N. Kilar and Y. Simsek, A new family of Fubini type numbers and polynomials associated with Apostol-Bernoulli numbers and polynomials, J. Korean Math. Soc. 54 (5) (2017) 1605-1621.
Programs
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Maple
F := proc(n,k) option remember; 1+k*add(binomial(n,j)*F(j,k),j=1..n-1) end: seq(print(seq(F(n-k,k),k=0..n)), n=0..7); # triangular form egf := k -> 1+1/(1/(exp(z)-1)-k): # egf of column k for k from 0 to 4 do seq(j!*coeff(series(egf(k),z,10),z,j),j=0..8) od; A := (n,k) -> `if`(n=0,1,add(k^(n-j-1)*(k+1)^j*combinat:-eulerian1(n,j),j=0..n-1)): seq(print(seq(A(n,k),k=0..5)),n=0..7);
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Mathematica
A[n_, k_] := A[n, k] = 1 + k Sum[Binomial[n, j] A[j, k], {j, 1, n - 1}]; Table[A[n - k, k], {n, 0, 10}, {k, 0, n}] // Flatten (* Jean-François Alcover, Mar 30 2016 *)
Formula
E.g.f. of column k: 1+1/(1/(exp(z)-1)-k).
A(n,k) = Sum_{j=0..n-1} k^j*j!*{n,j+1} for n>0, else 1; {n,j} denotes the Stirling subset numbers.
A(n,k) = Sum_{j=0..n-1} k^(n-j-1)*(k+1)^j* for n>0, else 1; denotes the Eulerian numbers.
Comments