Pyramid #374
Generating function
$$U_{374}(x, y) = - \frac{\left(y + 1\right)^{2}}{x - y - 1}$$
Explicit formula
$$T_{374}(n, m, k) = {\binom{k - n}{m}} {\binom{k + n - 1}{n}}$$
Data table
1 1 0 0 0 0 0
1 0 0 0 0 0 0
1 -1 1 -1 1 -1 1
1 -2 3 -4 5 -6 7
1 -3 6 -1 15 -21 28
1 -4 1 -2 35 -56 84
1 -5 15 -35 7 -126 21
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