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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 2 |
| 8 | 9 |
| 9 | 37 |
| 10 | 121 |
| 11 | 331 |
| 12 | 793 |
| 13 | 1718 |
| 14 | 3454 |
| 15 | 6646 |
| 16 | 12841 |
| 17 | 26589 |
| 18 | 61813 |
| 19 | 158918 |
| 20 | 426401 |
| 21 | 1134431 |
| 22 | 2914055 |
| 23 | 7171539 |
| 24 | 16967745 |
| 25 | 39008002 |
| 26 | 88529366 |
| 27 | 202057561 |
| 28 | 471422866 |
| 29 | 1133448790 |
| 30 | 2799775102 |
| 31 | 7026467132 |
| 32 | 17684574313 |
| 33 | 44192085565 |
| 34 | 109081884957 |
[1,1,1,1,1,1,1,2,9,37,121,331,793,1718,3454,6646, 12841,26589,61813,158918,426401,1134431,2914055, 7171539,16967745,39008002,88529366,202057561, 471422866,1133448790,2799775102,7026467132, 17684574313,44192085565,109081884957] |