Pyramid #513
Generating function
$$U_{513}(x, y) = \frac{x + \left(y + 1\right)^{3}}{\left(y + 1\right)^{2}}$$
Explicit formula
$$T_{513}(n, m, k) = {\binom{k}{n}} {\binom{k - 3 n}{m}}$$
Data table
1 1 0 0 0 0 0
1 -2 3 -4 5 -6 7
0 0 0 0 0 0 0
0 0 0 0 0 0 0
0 0 0 0 0 0 0
0 0 0 0 0 0 0
0 0 0 0 0 0 0
Export
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