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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 10 |
| 4 | 31 |
| 5 | 98 |
| 6 | 307 |
| 7 | 965 |
| 8 | 3031 |
| 9 | 9523 |
| 10 | 29917 |
| 11 | 93988 |
| 12 | 295272 |
| 13 | 927625 |
| 14 | 2914219 |
| 15 | 9155290 |
| 16 | 28762191 |
| 17 | 90359088 |
| 18 | 283871447 |
| 19 | 891808453 |
| 20 | 2801698884 |
| 21 | 8801796632 |
| 22 | 27651659637 |
| 23 | 86870250776 |
| 24 | 272910941653 |
| 25 | 857375009382 |
| 26 | 2693523030845 |
| 27 | 8461952165978 |
| 28 | 26584006759664 |
[1,3,10,31,98,307,965,3031,9523,29917,93988, 295272,927625,2914219,9155290,28762191,90359088, 283871447,891808453,2801698884,8801796632, 27651659637,86870250776,272910941653,857375009382, 2693523030845,8461952165978,26584006759664] |