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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 2 |
| 3 | 11 |
| 4 | 34 |
| 5 | 152 |
| 6 | 524 |
| 7 | 2207 |
| 8 | 7970 |
| 9 | 32744 |
| 10 | 121252 |
| 11 | 491988 |
| 12 | 1850380 |
| 13 | 7455944 |
| 14 | 28337976 |
| 15 | 113708295 |
| 16 | 435443490 |
| 17 | 1742630120 |
| 18 | 6711230900 |
| 19 | 26811568916 |
| 20 | 103711749284 |
| 21 | 413849297784 |
| 22 | 1606464657096 |
| 23 | 6405315809516 |
| 24 | 24935144010764 |
| 25 | 99367486347752 |
[0,1,2,11,34,152,524,2207,7970,32744,121252, 491988,1850380,7455944,28337976,113708295, 435443490,1742630120,6711230900,26811568916, 103711749284,413849297784,1606464657096, 6405315809516,24935144010764,99367486347752] |