A375600 Triangle read by rows: T(n, k) = n! * 3^k * hypergeom([-k], [-n], 2/3).
1, 1, 5, 2, 8, 34, 6, 22, 82, 314, 24, 84, 296, 1052, 3784, 120, 408, 1392, 4768, 16408, 56792, 720, 2400, 8016, 26832, 90032, 302912, 1022320, 5040, 16560, 54480, 179472, 592080, 1956304, 6474736, 21468848, 40320, 131040, 426240, 1387680, 4521984, 14750112, 48162944, 157438304, 515252608
Offset: 0
Examples
Triangle starts: [0] 1; [1] 1, 5; [2] 2, 8, 34; [3] 6, 22, 82, 314; [4] 24, 84, 296, 1052, 3784; [5] 120, 408, 1392, 4768, 16408, 56792; [6] 720, 2400, 8016, 26832, 90032, 302912, 1022320; [7] 5040, 16560, 54480, 179472, 592080, 1956304, 6474736, 21468848; ...
Programs
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Mathematica
T[n_, k_] := 2^k*Sum[(3/2)^(k - j)*Binomial[k, k - j]*((n - j)!), {j, 0, k}]; Table[T[n, k], {n, 0, 8}, {k, 0, n}] // Flatten
Formula
T(n, k) = 2^k*Sum_{j=0..k} (3/2)^(k - j)*binomial(k, k - j)*(n - j)!.