Pyramid #530
Generating function
$$U_{530}(x, y) = - \frac{1}{\left(1 - y\right)^{6} \left(x - \frac{1}{\left(1 - y\right)^{4}}\right)}$$
Explicit formula
$$T_{530}(n, m, k) = {\binom{k + n - 1}{n}} {\binom{2 k + m - 4 n - 1}{m}}$$
Data table
1 2 3 4 5 6 7
1 -2 1 0 0 0 0
1 -6 15 -2 15 -6 1
1 -1 45 -12 21 -252 21
1 -14 91 -364 1001 -2002 3003
1 -18 153 -816 306 -8568 18564
1 -22 231 -154 7315 -26334 74613
Export
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