Pyramid #730
Generating function
$$U_{730}(x, y) = \left(y + 1\right) \left(x \left(y + 1\right) + 1\right)^{3}$$
Explicit formula
$$T_{730}(n, m, k) = {\binom{3 k}{n}} {\binom{k + n}{m}}$$
Data table
1 1 0 0 0 0 0
3 6 3 0 0 0 0
3 9 9 3 0 0 0
1 4 6 4 1 0 0
0 0 0 0 0 0 0
0 0 0 0 0 0 0
0 0 0 0 0 0 0
Related
Export
expand_less