A193635 Triangle: T(n,k)=C(3n-k,k), 0<=k<=n.
1, 1, 2, 1, 5, 6, 1, 8, 21, 20, 1, 11, 45, 84, 70, 1, 14, 78, 220, 330, 252, 1, 17, 120, 455, 1001, 1287, 924, 1, 20, 171, 816, 2380, 4368, 5005, 3432, 1, 23, 231, 1330, 4845, 11628, 18564, 19448, 12870, 1, 26, 300, 2024, 8855, 26334, 54264, 77520, 75582
Offset: 0
Examples
First 5 rows of A193635: 1 1...2 1...7....10 1...15...66....82 1...26...231...811...930
Crossrefs
Cf. A193636.
Programs
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Mathematica
p[n_, k_] := Binomial[3 n - k, k]; Table[p[n, k], {n, 0, 9}, {k, 0, n}] (* A193635 *) Flatten[%]
Formula
T(n,k)=C(3n-k,k), 0<=k<=n.