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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 42 |
| 3 | 58 |
| 4 | 245 |
| 5 | 1382 |
| 6 | 9015 |
| 7 | 54361 |
| 8 | 338173 |
| 9 | 2152660 |
| 10 | 13818749 |
| 11 | 88065216 |
| 12 | 561506884 |
| 13 | 3594611840 |
| 14 | 22972741078 |
| 15 | 146835080662 |
| 16 | 938877932315 |
| 17 | 6002943788616 |
| 18 | 38380680312986 |
| 19 | 245393290686015 |
| 20 | 1569003851769309 |
| 21 | 10031859337955923 |
[1,42,58,245,1382,9015,54361,338173,2152660, 13818749,88065216,561506884,3594611840, 22972741078,146835080662,938877932315, 6002943788616,38380680312986,245393290686015, 1569003851769309,10031859337955923] |