Generating function
$$U_{1452}(x, y) = \frac{1 - \sqrt{- \frac{4 x}{\left(1 - y\right)^{2}} + 1}}{2 x \left(1 - y\right)}$$
Explicit formula
$$T_{1452}(n, m, k) = \frac{k {\binom{k + 2 n - 1}{n}} {\binom{3 k + m + 2 n - 1}{m}}}{k + n}$$
Data table
1 3 6 1 15 21 28
1 5 15 35 7 126 21
2 14 56 168 42 924 1848
5 45 225 825 2475 6435 15015
14 154 924 4004 14014 42042 112112
42 546 3822 1911 7644 259896 779688
132 198 1584 8976 40392 1534896 511632
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