OFFSET
0,8
LINKS
Seiichi Manyama, Antidiagonals n = 0..139, flattened
FORMULA
A(0,k) = 1 and A(n,k) = -k * Sum_{j=0..n-1} binomial(n-1,j) * A(j,k) for n > 0.
A(n,k) = Sum_{j=0..n} (-k)^j * Stirling2(n,j). - Seiichi Manyama, Jul 27 2019
A(n,k) = BellPolynomial(n, -k). - Peter Luschny, Dec 23 2021
EXAMPLE
Square array begins:
1, 1, 1, 1, 1, 1, 1, ...
0, -1, -2, -3, -4, -5, -6, ...
0, 0, 2, 6, 12, 20, 30, ...
0, 1, 2, -3, -20, -55, -114, ...
0, 1, -6, -21, -20, 45, 246, ...
0, -2, -14, 24, 172, 370, 318, ...
0, -9, 26, 195, 108, -1105, -4074, ...
MAPLE
A:= proc(n, k) option remember; `if`(n=0, 1,
-(1+add(binomial(n-1, j-1)*A(n-j, k), j=1..n-1))*k)
end:
seq(seq(A(n, d-n), n=0..d), d=0..12); # Alois P. Heinz, Sep 25 2017
MATHEMATICA
A[n_, k_] := Sum[(-k)^j StirlingS2[n, j], {j, 0, n}];
Table[A[n, d-n], {d, 0, 12}, {n, 0, d}] // Flatten (* Jean-François Alcover, Feb 10 2021 *)
A292861[n_, k_] := BellB[k, k - n];
Table[A292861[n, k], {n, 0, 11}, {k, 0, n}] // Flatten (* Peter Luschny, Dec 23 2021 *)
CROSSREFS
AUTHOR
Seiichi Manyama, Sep 25 2017
STATUS
approved