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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 8 |
| 6 | 17 |
| 7 | 37 |
| 8 | 81 |
| 9 | 180 |
| 10 | 405 |
| 11 | 917 |
| 12 | 2090 |
| 13 | 4795 |
| 14 | 11054 |
| 15 | 25589 |
| 16 | 59475 |
| 17 | 138712 |
| 18 | 324483 |
| 19 | 761163 |
| 20 | 1790028 |
| 21 | 4219139 |
| 22 | 9965328 |
| 23 | 23582735 |
| 24 | 55906518 |
| 25 | 132751359 |
| 26 | 315700152 |
| 27 | 751837207 |
| 28 | 1792853416 |
| 29 | 4280568845 |
| 30 | 10232005939 |
| 31 | 24484563844 |
| 32 | 58650123942 |
| 33 | 140625967460 |
| 34 | 337488663293 |
| 35 | 810641635789 |
[1,1,1,2,4,8,17,37,81,180,405,917,2090,4795,11054, 25589,59475,138712,324483,761163,1790028,4219139, 9965328,23582735,55906518,132751359,315700152, 751837207,1792853416,4280568845,10232005939, 24484563844,58650123942,140625967460,337488663293, 810641635789] |