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| n | a(n) |
|---|---|
| 1 | 10 |
| 2 | 25 |
| 3 | 315 |
| 4 | 2275 |
| 5 | 15256 |
| 6 | 88117 |
| 7 | 471820 |
| 8 | 2391887 |
| 9 | 11508779 |
| 10 | 52475021 |
| 11 | 227321634 |
| 12 | 940155612 |
| 13 | 3730532377 |
| 14 | 14259828254 |
| 15 | 52676081028 |
| 16 | 188532399603 |
| 17 | 655195900069 |
| 18 | 2215012029848 |
| 19 | 7296267122433 |
| 20 | 23450719844938 |
| 21 | 73634389866258 |
[10,25,315,2275,15256,88117,471820,2391887, 11508779,52475021,227321634,940155612,3730532377, 14259828254,52676081028,188532399603,655195900069, 2215012029848,7296267122433,23450719844938, 73634389866258] |