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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 6 |
| 5 | 15 |
| 6 | 34 |
| 7 | 75 |
| 8 | 162 |
| 9 | 337 |
| 10 | 706 |
| 11 | 1466 |
| 12 | 2995 |
| 13 | 6119 |
| 14 | 12450 |
| 15 | 25248 |
| 16 | 51158 |
| 17 | 103450 |
| 18 | 209010 |
| 19 | 421681 |
| 20 | 850322 |
| 21 | 1712673 |
| 22 | 3447970 |
| 23 | 6937759 |
| 24 | 13952296 |
| 25 | 28049834 |
| 26 | 56369395 |
| 27 | 113241087 |
| 28 | 227428919 |
| 29 | 456641954 |
| 30 | 916642515 |
| 31 | 1839651364 |
| 32 | 3691364919 |
| 33 | 7405635242 |
[1,1,2,6,15,34,75,162,337,706,1466,2995,6119, 12450,25248,51158,103450,209010,421681,850322, 1712673,3447970,6937759,13952296,28049834, 56369395,113241087,227428919,456641954,916642515, 1839651364,3691364919,7405635242] |