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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 5 |
| 4 | 7 |
| 5 | 42 |
| 6 | 22 |
| 7 | 429 |
| 8 | 715 |
| 9 | 4862 |
| 10 | 8398 |
| 11 | 58786 |
| 12 | 52003 |
| 13 | 742900 |
| 14 | 1337220 |
| 15 | 646323 |
| 16 | 17678835 |
| 17 | 129644790 |
| 18 | 79606450 |
| 19 | 1767263190 |
| 20 | 328206021 |
| 21 | 8155422340 |
| 22 | 45741281820 |
| 23 | 343059613650 |
| 24 | 107492012277 |
| 25 | 4861946401452 |
| 26 | 9183676536076 |
[1,1,1,5,7,42,22,429,715,4862,8398,58786,52003, 742900,1337220,646323,17678835,129644790,79606450, 1767263190,328206021,8155422340,45741281820, 343059613650,107492012277,4861946401452, 9183676536076] |