A371026 Triangle read by rows: T(n, k) = 4^n*Sum_{j=0..k} (-1)^(k - j)*binomial(k, j)* Pochhammer(j/4, n).
1, 0, 1, 0, 5, 2, 0, 45, 30, 6, 0, 585, 510, 180, 24, 0, 9945, 10350, 4950, 1200, 120, 0, 208845, 247590, 144900, 48600, 9000, 720, 0, 5221125, 6855030, 4655070, 1940400, 504000, 75600, 5040, 0, 151412625, 216093150, 164872260, 80713080, 26334000, 5594400, 705600, 40320
Offset: 0
Examples
Triangle read by rows: [0] 1; [1] 0, 1; [2] 0, 5, 2; [3] 0, 45, 30, 6; [4] 0, 585, 510, 180, 24; [5] 0, 9945, 10350, 4950, 1200, 120; [6] 0, 208845, 247590, 144900, 48600, 9000, 720; [7] 0, 5221125, 6855030, 4655070, 1940400, 504000, 75600, 5040;
Programs
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Maple
A371026 := (n, k) -> local j; 4^n*add((-1)^(k - j)*binomial(k, j)*pochhammer(j/4, n), j = 0..k): seq(seq(A371026(n, k), k = 0..n), n = 0..9);
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Python
from functools import cache @cache def T(n, k): # After Werner Schulte if k == 0: return 0**n if k == n: return n * T(n-1, n-1) return k * T(n-1, k-1) + (4*n - 4 + k) * T(n-1, k) for n in range(8): print([T(n, k) for k in range(n + 1)]) # Peter Luschny, Mar 17 2024
Formula
T(n, k) = k * T(n-1, k-1) + (4*n - 4 + k) * T(n-1, k) for 0 < k < n with initial values T(n, 0) = 0 for n > 0 and T(n, n) = n! for n >= 0. - Werner Schulte, Mar 17 2024