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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 2 |
| 5 | 5 |
| 6 | 5 |
| 7 | 15 |
| 8 | 15 |
| 9 | 52 |
| 10 | 52 |
| 11 | 203 |
| 12 | 203 |
| 13 | 876 |
| 14 | 876 |
| 15 | 4111 |
| 16 | 4111 |
| 17 | 20648 |
| 18 | 20648 |
| 19 | 109299 |
| 20 | 109299 |
| 21 | 601492 |
| 22 | 601492 |
| 23 | 3403127 |
| 24 | 3403127 |
| 25 | 19628064 |
| 26 | 19628064 |
| 27 | 114700315 |
| 28 | 114700315 |
| 29 | 676207628 |
| 30 | 676207628 |
| 31 | 4010090463 |
[1,1,2,2,5,5,15,15,52,52,203,203,876,876,4111, 4111,20648,20648,109299,109299,601492,601492, 3403127,3403127,19628064,19628064,114700315, 114700315,676207628,676207628,4010090463] |