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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 3 |
| 4 | 4 |
| 5 | 56 |
| 6 | 67 |
| 7 | 670 |
| 8 | 7740 |
| 9 | 41842 |
| 10 | 47345 |
| 11 | 89440 |
| 12 | 93196 |
| 13 | 189277 |
| 14 | 247372 |
| 15 | 321327 |
| 16 | 474346 |
| 17 | 826237 |
| 18 | 1988987 |
| 19 | 2364721 |
| 20 | 2886736 |
| 21 | 2937246 |
| 22 | 5426145 |
| 23 | 12969551 |
| 24 | 34658342 |
| 25 | 109686031 |
| 26 | 373121462 |
| 27 | 681070488 |
| 28 | 1000410504 |
| 29 | 4064275165 |
[0,1,3,4,56,67,670,7740,41842,47345,89440,93196, 189277,247372,321327,474346,826237,1988987, 2364721,2886736,2937246,5426145,12969551,34658342, 109686031,373121462,681070488,1000410504, 4064275165] |