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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 7 |
| 3 | 13 |
| 4 | 23 |
| 5 | 47 |
| 6 | 144 |
| 7 | 391 |
| 8 | 1118 |
| 9 | 3330 |
| 10 | 10129 |
| 11 | 30953 |
| 12 | 95037 |
| 13 | 293116 |
| 14 | 905585 |
| 15 | 2799778 |
| 16 | 8662028 |
| 17 | 26809369 |
| 18 | 82990751 |
| 19 | 256933941 |
| 20 | 795508636 |
| 21 | 2463117879 |
| 22 | 7626665518 |
| 23 | 23615103348 |
| 24 | 73122045417 |
| 25 | 226416803035 |
| 26 | 701083972797 |
| 27 | 2170861196560 |
[1,7,13,23,47,144,391,1118,3330,10129,30953,95037, 293116,905585,2799778,8662028,26809369,82990751, 256933941,795508636,2463117879,7626665518, 23615103348,73122045417,226416803035,701083972797, 2170861196560] |