Generating function
$$U_{1224}(x, y) = \frac{\frac{\sin{\left(\frac{\operatorname{asin}{\left(216 y^{2} - 1 \right)}}{3} \right)}}{6 y} + \frac{1}{12 y}}{\left(1 - x\right)^{3}}$$
Explicit formula
$$T_{1224}(n, m, k) = \begin{cases}1&\text{if n=0 , m=0 , k=0} ,\ \\\frac{4^{m} k {\binom{\frac{k}{2} + \frac{3 m}{2} - 1}{m}} {\binom{3 k + n - 1}{n}}}{k + m}&\text{if k even} ,\ \\\frac{k {\binom{\frac{k}{2} + \frac{3 m}{2} - \frac{1}{2}}{m}} {\binom{k + 3 m - 1}{\frac{k}{2} + \frac{3 m}{2} - \frac{1}{2}}} {\binom{3 k + n - 1}{n}}}{\left(k + m\right) {\binom{k + m - 1}{\frac{k}{2} + \frac{m}{2} - \frac{1}{2}}}}&\text{if k odd} \end{cases} $$
1 | 1.5 | 10 | 42 | 462 | 2252.25 | 29172 |
3 | 4.5 | 30 | 126 | 1386 | 6756.75 | 87516 |
6 | 9 | 60 | 252 | 2772 | 13513.5 | 175032 |
10 | 15 | 100 | 420 | 4620 | 22522.5 | 291720 |
15 | 22.5 | 150 | 630 | 6930 | 33783.75 | 437580 |
21 | 31.5 | 210 | 882 | 9702 | 47297.25 | 612612 |
28 | 42 | 280 | 1176 | 12936 | 63063 | 816816 |
Related
Export
Export as LaTeX
Export as Maxima
Confirm deletion
Are you sure, you want to delete Pyramid #1224?