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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 14 |
| 4 | 30 |
| 5 | 68 |
| 6 | 145 |
| 7 | 298 |
| 8 | 600 |
| 9 | 1182 |
| 10 | 2280 |
| 11 | 4318 |
| 12 | 8064 |
| 13 | 14824 |
| 14 | 26917 |
| 15 | 48292 |
| 16 | 85675 |
| 17 | 150466 |
| 18 | 261762 |
| 19 | 451328 |
| 20 | 771739 |
| 21 | 1309362 |
| 22 | 2205109 |
| 23 | 3687904 |
| 24 | 6127155 |
| 25 | 10116074 |
| 26 | 16602508 |
| 27 | 27093582 |
| 28 | 43974355 |
| 29 | 71003224 |
[1,2,5,14,30,68,145,298,600,1182,2280,4318,8064, 14824,26917,48292,85675,150466,261762,451328, 771739,1309362,2205109,3687904,6127155,10116074, 16602508,27093582,43974355,71003224] |