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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 5 |
| 5 | 12 |
| 6 | 26 |
| 7 | 63 |
| 8 | 153 |
| 9 | 385 |
| 10 | 979 |
| 11 | 2520 |
| 12 | 6524 |
| 13 | 16965 |
| 14 | 44225 |
| 15 | 115479 |
| 16 | 301833 |
| 17 | 789412 |
| 18 | 2065414 |
| 19 | 5405235 |
| 20 | 14147705 |
| 21 | 37033701 |
| 22 | 96946631 |
| 23 | 253795248 |
| 24 | 664421400 |
| 25 | 1739440297 |
| 26 | 4553853121 |
| 27 | 11922044043 |
| 28 | 31212157613 |
| 29 | 81714232380 |
| 30 | 213930221714 |
[1,1,3,5,12,26,63,153,385,979,2520,6524,16965, 44225,115479,301833,789412,2065414,5405235, 14147705,37033701,96946631,253795248,664421400, 1739440297,4553853121,11922044043,31212157613, 81714232380,213930221714] |