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| n | a(n) |
|---|---|
| 2 | 1 |
| 3 | 3 |
| 4 | 10 |
| 5 | 24 |
| 6 | 62 |
| 7 | 140 |
| 8 | 329 |
| 9 | 725 |
| 10 | 1631 |
| 11 | 3548 |
| 12 | 7820 |
| 13 | 16887 |
| 14 | 36767 |
| 15 | 79046 |
| 16 | 170799 |
| 17 | 365883 |
| 18 | 786361 |
| 19 | 1679486 |
| 20 | 3594580 |
| 21 | 7656839 |
| 22 | 16331933 |
| 23 | 34705064 |
| 24 | 73810524 |
| 25 | 156501393 |
| 26 | 332001987 |
| 27 | 702530049 |
| 28 | 1486995062 |
| 29 | 3140712201 |
| 30 | 6634309660 |
| 31 | 13988510961 |
| 32 | 29494808402 |
| 33 | 62091823865 |
[1,3,10,24,62,140,329,725,1631,3548,7820,16887, 36767,79046,170799,365883,786361,1679486,3594580, 7656839,16331933,34705064,73810524,156501393, 332001987,702530049,1486995062,3140712201, 6634309660,13988510961,29494808402,62091823865] |