Pyramid #1399
Pyramid #1400
Pyramid #1401
Generating function
$$U_{1400}(x, y) = y \left(x + 1\right)^{2} + 1$$
Explicit formula
$$T_{1400}(n, m, k) = {\binom{k}{m}} {\binom{2 m}{n}}$$
Data table
1 1 0 0 0 0 0
0 2 0 0 0 0 0
0 1 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
Related
Pyramid #148: Change x y
Export
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