Generating function
$$U_{1180}(x, y) = \left(y + 1\right) \sqrt{4 x \left(y + 1\right)^{2} + 1}$$
Explicit formula
$$Tsqrt(n, k) = \begin{cases}\binom{m}{n} 4^{n}&\text{if k even, where m =} \frac{k} {2},\\\frac {{(-1)}^{n-m} \binom{n}{m} \binom{2n}{n}} {\binom{2n}{2m}} &\text{if k odd, n > m, where m =} \frac{k+1} {2},\\\frac {\binom{2m}{2n} \binom{2n}{n}} {\binom{m}{n}}&\text{if k odd, n} \le \text{m, where m =} \frac{k+1} {2},\\\end{cases} $$$$T_{1180}(n, m, k) = \operatorname{Tsqrt}{\left(n,k \right)} {\binom{k + 2 n}{m}}$$
Data table
1 1 0 0 0 0 0
2 6 6 2 0 0 0
-2 -10 -20 -20 -10 -2 0
4 28 84 140 140 84 28
-10 -90 -360 -840 -1260 -1260 -840
28 308 1540 4620 9240 12936 12936
-84 -1092 -6552 -24024 -60060 -108108 -144144
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