Pyramid #141
Generating function
$$U_{141}(x, y) = \frac{- x + \sqrt{x^{2} + 2 x + y \left(4 x + 4\right) + 1} - 1}{y \left(2 x + 2\right)}$$
Explicit formula
$$T_{141}(n, m, k) = \frac{\left(-1\right)^{m + n} k {\binom{k + 2 m - 1}{m}} {\binom{k + m + n - 1}{n}}}{k + m}$$
Data table
1 -1 2 -5 14 -42 132
-1 2 -6 2 -7 252 -924
1 -3 12 -5 21 -882 3696
-1 4 -2 1 -49 2352 -11088
1 -5 3 -175 98 -5292 2772
-1 6 -42 28 -1764 10584 -60984
1 -7 56 -42 294 -19404 121968
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