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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 8 |
| 4 | 19 |
| 5 | 40 |
| 6 | 86 |
| 7 | 181 |
| 8 | 383 |
| 9 | 811 |
| 10 | 1709 |
| 11 | 3598 |
| 12 | 7554 |
| 13 | 15839 |
| 14 | 33158 |
| 15 | 69319 |
| 16 | 144731 |
| 17 | 301813 |
| 18 | 628727 |
| 19 | 1308487 |
| 20 | 2720908 |
| 21 | 5653743 |
| 22 | 11740260 |
| 23 | 24365703 |
| 24 | 50544832 |
| 25 | 104810967 |
| 26 | 217270721 |
| 27 | 450287996 |
| 28 | 933043086 |
| 29 | 1933125817 |
| 30 | 4004865745 |
| 31 | 8296690701 |
| 32 | 17188106646 |
| 33 | 35609996584 |
[1,2,4,8,19,40,86,181,383,811,1709,3598,7554, 15839,33158,69319,144731,301813,628727,1308487, 2720908,5653743,11740260,24365703,50544832, 104810967,217270721,450287996,933043086, 1933125817,4004865745,8296690701,17188106646, 35609996584] |