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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 7 |
| 3 | 43 |
| 4 | 277 |
| 5 | 1777 |
| 6 | 11407 |
| 7 | 73219 |
| 8 | 469981 |
| 9 | 3016729 |
| 10 | 19363879 |
| 11 | 124293499 |
| 12 | 797819173 |
| 13 | 5121067777 |
| 14 | 32871277183 |
| 15 | 210995228083 |
| 16 | 1354343064493 |
| 17 | 8693301516841 |
| 18 | 55800847838359 |
| 19 | 358176305451691 |
| 20 | 2299073773191541 |
| 21 | 14757369859827601 |
| 22 | 94725087867636847 |
[1,7,43,277,1777,11407,73219,469981,3016729, 19363879,124293499,797819173,5121067777, 32871277183,210995228083,1354343064493, 8693301516841,55800847838359,358176305451691, 2299073773191541,14757369859827601, 94725087867636847] |