Pyramid #673
Generating function
$$U_{673}(x, y) = \frac{x}{\left(1 - y\right)^{2}} + 1$$
Explicit formula
$$T_{673}(n, m, k) = {\binom{k}{n}} {\binom{m + 2 n - 1}{m}}$$
Data table
1 0 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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