Pyramid #967
Generating function
$$U_{967}(x, y) = \frac{- x - \sqrt{- 4 x^{2} y + x^{2} - 2 x + 1} + 1}{2 x^{2} y}$$
Explicit formula
$$T_{967}(n, m, k) = \frac{k {\binom{k + n}{- m + n}} {\binom{- m + n}{m}}}{k + n}$$
Data table
1 0 0 0 0 0 0
1 0 0 0 0 0 0
1 1 0 0 0 0 0
1 3 0 0 0 0 0
1 6 2 0 0 0 0
1 1 1 0 0 0 0
1 15 3 5 0 0 0
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