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| n | a(n) |
|---|---|
| 1 | 40 |
| 2 | 1892 |
| 3 | 27508 |
| 4 | 182634 |
| 5 | 787412 |
| 6 | 2642358 |
| 7 | 7269852 |
| 8 | 17692662 |
| 9 | 38791846 |
| 10 | 78583484 |
| 11 | 149461616 |
| 12 | 269390980 |
| 13 | 462294730 |
| 14 | 765448244 |
| 15 | 1224516760 |
| 16 | 1898713570 |
| 17 | 2870678078 |
| 18 | 4243248920 |
| 19 | 6141093956 |
| 20 | 8731426052 |
| 21 | 12179866066 |
| 22 | 16758644852 |
[40,1892,27508,182634,787412,2642358,7269852, 17692662,38791846,78583484,149461616,269390980, 462294730,765448244,1224516760,1898713570, 2870678078,4243248920,6141093956,8731426052, 12179866066,16758644852] |