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| n | a(n) |
|---|---|
| 1 | 721 |
| 2 | 3437 |
| 3 | 16660 |
| 4 | 80132 |
| 5 | 376559 |
| 6 | 1782453 |
| 7 | 8476317 |
| 8 | 40313706 |
| 9 | 191370192 |
| 10 | 908268343 |
| 11 | 4312922647 |
| 12 | 20483132941 |
| 13 | 97267496309 |
| 14 | 461856616822 |
| 15 | 2193101268453 |
| 16 | 10414092378458 |
| 17 | 49451882143389 |
| 18 | 234822848509532 |
| 19 | 1115058584108581 |
[721,3437,16660,80132,376559,1782453,8476317, 40313706,191370192,908268343,4312922647, 20483132941,97267496309,461856616822, 2193101268453,10414092378458,49451882143389, 234822848509532,1115058584108581] |