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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 69 |
| 6 | 1132 |
| 7 | 7235 |
| 8 | 25233 |
| 9 | 63135 |
| 10 | 129133 |
| 11 | 231419 |
| 12 | 378185 |
| 13 | 577623 |
| 14 | 837925 |
| 15 | 1167283 |
| 16 | 1573889 |
| 17 | 2065935 |
| 18 | 2651613 |
| 19 | 3339115 |
| 20 | 4136633 |
| 21 | 5052359 |
| 22 | 6094485 |
| 23 | 7271203 |
| 24 | 8590705 |
| 25 | 10061183 |
| 26 | 11690829 |
| 27 | 13487835 |
| 28 | 15460393 |
| 29 | 17616695 |
| 30 | 19964933 |
| 31 | 22513299 |
[1,1,1,1,69,1132,7235,25233,63135,129133,231419, 378185,577623,837925,1167283,1573889,2065935, 2651613,3339115,4136633,5052359,6094485,7271203, 8590705,10061183,11690829,13487835,15460393, 17616695,19964933,22513299] |