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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 11 |
| 4 | 100 |
| 5 | 1269 |
| 6 | 20680 |
| 7 | 411655 |
| 8 | 9681040 |
| 9 | 262644825 |
| 10 | 8074470560 |
| 11 | 277410402675 |
| 12 | 10533370203200 |
| 13 | 438024379604525 |
| 14 | 19798139730512000 |
| 15 | 966408931916064975 |
| 16 | 50666524133429152000 |
| 17 | 2839464166814487200625 |
| 18 | 169393547843598544960000 |
| 19 | 10717798206604377757886875 |
[1,2,11,100,1269,20680,411655,9681040,262644825, 8074470560,277410402675,10533370203200, 438024379604525,19798139730512000, 966408931916064975,50666524133429152000, 2839464166814487200625,169393547843598544960000, 10717798206604377757886875] |