Pyramid #519
Generating function
$$U_{519}(x, y) = \frac{x + \left(y + 1\right)^{6}}{\left(y + 1\right)^{4}}$$
Explicit formula
$$T_{519}(n, m, k) = {\binom{k}{n}} {\binom{2 k - 6 n}{m}}$$
Data table
1 2 1 0 0 0 0
1 -4 1 -2 35 -56 84
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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