Pyramid #434
Generating function
$$U_{434}(x, y) = \frac{x^{2} - 2 x + y + 1}{x^{4} - 4 x^{3} + 6 x^{2} - 4 x + 1}$$
Explicit formula
$$T_{434}(n, m, k) = {\binom{k}{m}} {\binom{2 k + 2 m + n - 1}{n}}$$
Data table
1 1 0 0 0 0 0
2 4 0 0 0 0 0
3 1 0 0 0 0 0
4 2 0 0 0 0 0
5 35 0 0 0 0 0
6 56 0 0 0 0 0
7 84 0 0 0 0 0
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