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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 12 |
| 5 | 25 |
| 6 | 97 |
| 7 | 217 |
| 8 | 984 |
| 9 | 2409 |
| 10 | 10215 |
| 11 | 25487 |
| 12 | 118874 |
| 13 | 312013 |
| 14 | 1396444 |
| 15 | 3700827 |
| 16 | 17618644 |
| 17 | 48201953 |
| 18 | 221644603 |
| 19 | 608941279 |
| 20 | 2931135298 |
| 21 | 8236542965 |
| 22 | 38529196470 |
| 23 | 108470810209 |
| 24 | 526019556566 |
| 25 | 1506349925585 |
| 26 | 7129197496267 |
| 27 | 20427829442487 |
| 28 | 99578663297064 |
| 29 | 289201492121849 |
| 30 | 1380244537295549 |
| 31 | 4008026266125961 |
[1,1,2,3,12,25,97,217,984,2409,10215,25487,118874, 312013,1396444,3700827,17618644,48201953, 221644603,608941279,2931135298,8236542965, 38529196470,108470810209,526019556566, 1506349925585,7129197496267,20427829442487, 99578663297064,289201492121849,1380244537295549, 4008026266125961] |