Generating function
$$U_{1075}(x, y) = \sqrt{4 x \left(y + 1\right)^{3} + 1}$$
Explicit formula
$$Tsqrt(n, k) = \begin{cases}\binom{m}{n} 4^{n}&\text{if k even, where m =} \frac{k} {2},\\\frac {{(-1)}^{n-m} \binom{n}{m} \binom{2n}{n}} {\binom{2n}{2m}} &\text{if k odd, n > m, where m =} \frac{k+1} {2},\\\frac {\binom{2m}{2n} \binom{2n}{n}} {\binom{m}{n}}&\text{if k odd, n} \le \text{m, where m =} \frac{k+1} {2},\\\end{cases} $$$$T_{1075}(n, m, k) = k \operatorname{Tsqrt}{\left(n,k \right)} {\binom{3 n}{m}}$$
Data table
1 0 0 0 0 0 0
2 6 6 2 0 0 0
-2 -12 -30 -40 -30 -12 -2
4 36 144 336 504 504 336
-10 -120 -660 -2200 -4950 -7920 -9240
28 420 2940 12740 38220 84084 140140
-84 -1512 -12852 -68544 -257040 -719712 -1559376
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