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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 2 |
| 4 | 6 |
| 5 | 13 |
| 6 | 25 |
| 7 | 51 |
| 8 | 113 |
| 9 | 264 |
| 10 | 478 |
| 11 | 957 |
| 12 | 1925 |
| 13 | 3888 |
| 14 | 7989 |
| 15 | 16671 |
| 16 | 36273 |
| 17 | 85329 |
| 18 | 153988 |
| 19 | 307977 |
| 20 | 615965 |
| 21 | 1231968 |
| 22 | 2464149 |
| 23 | 4928991 |
| 24 | 9860913 |
| 25 | 19734609 |
| 26 | 39537876 |
| 27 | 79298400 |
| 28 | 159520791 |
| 29 | 322738605 |
| 30 | 660282828 |
| 31 | 1380129447 |
| 32 | 3003699099 |
[1,2,2,6,13,25,51,113,264,478,957,1925,3888,7989, 16671,36273,85329,153988,307977,615965,1231968, 2464149,4928991,9860913,19734609,39537876, 79298400,159520791,322738605,660282828,1380129447, 3003699099] |