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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 69 |
| 3 | 1064 |
| 4 | 8736 |
| 5 | 49350 |
| 6 | 216342 |
| 7 | 787968 |
| 8 | 2489448 |
| 9 | 7024407 |
| 10 | 18074875 |
| 11 | 43072848 |
| 12 | 96186272 |
| 13 | 203145852 |
| 14 | 408774588 |
| 15 | 788378400 |
| 16 | 1464523344 |
| 17 | 2631173181 |
| 18 | 4587701601 |
| 19 | 7785938104 |
| 20 | 12894168000 |
| 21 | 20882898530 |
| 22 | 33138238770 |
[1,69,1064,8736,49350,216342,787968,2489448, 7024407,18074875,43072848,96186272,203145852, 408774588,788378400,1464523344,2631173181, 4587701601,7785938104,12894168000,20882898530, 33138238770] |