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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 14 |
| 3 | 77 |
| 4 | 451 |
| 5 | 2728 |
| 6 | 16834 |
| 7 | 105317 |
| 8 | 665551 |
| 9 | 4238463 |
| 10 | 27156744 |
| 11 | 174858972 |
| 12 | 1130494236 |
| 13 | 7333934988 |
| 14 | 47717158394 |
| 15 | 311248100517 |
| 16 | 2034664811631 |
| 17 | 13326556644753 |
| 18 | 87435235471214 |
| 19 | 574537592170357 |
| 20 | 3780472550923091 |
| 21 | 24906432444097408 |
| 22 | 164272522873515704 |
[1,3,14,77,451,2728,16834,105317,665551,4238463, 27156744,174858972,1130494236,7333934988, 47717158394,311248100517,2034664811631, 13326556644753,87435235471214,574537592170357, 3780472550923091,24906432444097408, 164272522873515704] |