OFFSET
0,4
EXAMPLE
Triangle starts:
1;
1, 1;
-2, -1, 1;
6, 2, -3, 1;
-22, -6, 10, -5, 1;
90, 22, -38, 22, -7, 1;
...
MATHEMATICA
T[n_, k_]:=SeriesCoefficient[(1-x+Sqrt[1+6x+x^2])((Sqrt[1+6x+x^2]-x-1)/2)^k/2, {x, 0, n}]; Table[T[n, k], {n, 0, 9}, {k, 0, n}]//Flatten (* Stefano Spezia, May 26 2024 *)
CROSSREFS
KEYWORD
AUTHOR
Paul Barry, Sep 07 2005
STATUS
approved