A326723 Triangle read by rows: T(n, k) = (-1)^(n - k) * binomial(n, k) * A000182(n).
0, -1, 1, 2, -4, 2, -16, 48, -48, 16, 272, -1088, 1632, -1088, 272, -7936, 39680, -79360, 79360, -39680, 7936, 353792, -2122752, 5306880, -7075840, 5306880, -2122752, 353792, -22368256, 156577792, -469733376, 782888960, -782888960, 469733376, -156577792, 22368256
Offset: 0
Examples
Triangle starts: [0] 0; [1] -1, 1; [2] 2, -4, 2; [3] -16, 48, -48, 16; [4] 272, -1088, 1632, -1088, 272; [5] -7936, 39680, -79360, 79360, -39680, 7936; [6] 353792, -2122752, 5306880, -7075840, 5306880, -2122752, 353792;
Programs
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Maple
T := (n, k) -> (-1)^(n - k)*binomial(n, k)*A000182(n): seq(seq(T(n, k), k = 0..n), n = 0..6); # Peter Luschny, Apr 23 2024
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Mathematica
gf := Sqrt[x - 1] Tan[y Sqrt[x - 1]]; ser := Series[gf, {y, 0, 26}]; cy[n_] := n! Coefficient[ser, y, n]; row[n_] := If[n == 0, 0, CoefficientList[cy[2 n - 1], x]]; Table[row[n], {n, 0, 7}] // Flatten
Formula
T(n, k) = (2*n-1)! [x^k] [y^(2*n-1)] sqrt(x - 1)*tan(y*sqrt(x - 1)) for n > 0.
Sum_{k=0..n} (-1)^(n-k)*T(n, k) = 2*A261042(n-1) for n > 0.
Extensions
Offset set to 0, T(0,0) = 0 and new name by Peter Luschny, Apr 23 2024