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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 6 |
| 3 | 13 |
| 4 | 27 |
| 5 | 54 |
| 6 | 106 |
| 7 | 204 |
| 8 | 387 |
| 9 | 725 |
| 10 | 1344 |
| 11 | 2469 |
| 12 | 4500 |
| 13 | 8145 |
| 14 | 14652 |
| 15 | 26213 |
| 16 | 46665 |
| 17 | 82704 |
| 18 | 145982 |
| 19 | 256722 |
| 20 | 449937 |
| 21 | 786109 |
| 22 | 1369494 |
| 23 | 2379447 |
| 24 | 4123944 |
| 25 | 7130895 |
| 26 | 12303714 |
| 27 | 21186013 |
| 28 | 36411399 |
| 29 | 62466906 |
| 30 | 106987282 |
| 31 | 182946888 |
| 32 | 312367887 |
| 33 | 532587461 |
| 34 | 906840060 |
[1,3,6,13,27,54,106,204,387,725,1344,2469,4500, 8145,14652,26213,46665,82704,145982,256722,449937, 786109,1369494,2379447,4123944,7130895,12303714, 21186013,36411399,62466906,106987282,182946888, 312367887,532587461,906840060] |