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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 2 |
| 3 | 5 |
| 4 | 9 |
| 5 | 14 |
| 6 | 42 |
| 7 | 42 |
| 8 | 168 |
| 9 | 504 |
| 10 | 2520 |
| 11 | 2531 |
| 12 | 2543 |
| 13 | 2556 |
| 14 | 17892 |
| 15 | 89460 |
| 16 | 357840 |
| 17 | 357857 |
| 18 | 357875 |
| 19 | 357894 |
| 20 | 3578940 |
| 21 | 25052580 |
| 22 | 275578380 |
| 23 | 275578403 |
| 24 | 275578427 |
| 25 | 275578452 |
| 26 | 3582519876 |
| 27 | 10747559628 |
| 28 | 75232917396 |
| 29 | 75232917425 |
| 30 | 451397504550 |
[1,2,2,5,9,14,42,42,168,504,2520,2531,2543,2556, 17892,89460,357840,357857,357875,357894,3578940, 25052580,275578380,275578403,275578427,275578452, 3582519876,10747559628,75232917396,75232917425, 451397504550] |