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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 12 |
| 4 | 30 |
| 5 | 75 |
| 6 | 190 |
| 7 | 484 |
| 8 | 1242 |
| 9 | 3206 |
| 10 | 8316 |
| 11 | 21657 |
| 12 | 56591 |
| 13 | 148303 |
| 14 | 389615 |
| 15 | 1025810 |
| 16 | 2706014 |
| 17 | 7150411 |
| 18 | 18923033 |
| 19 | 50146688 |
| 20 | 133054093 |
| 21 | 353426693 |
| 22 | 939750924 |
| 23 | 2501100209 |
| 24 | 6662258807 |
| 25 | 17760491578 |
| 26 | 47381172431 |
| 27 | 126488492584 |
[1,2,5,12,30,75,190,484,1242,3206,8316,21657, 56591,148303,389615,1025810,2706014,7150411, 18923033,50146688,133054093,353426693,939750924, 2501100209,6662258807,17760491578,47381172431, 126488492584] |