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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 10 |
| 2 | 145 |
| 3 | 2120 |
| 4 | 29660 |
| 5 | 406752 |
| 6 | 5475160 |
| 7 | 72591320 |
| 8 | 950032770 |
| 9 | 12294612660 |
| 10 | 157545928646 |
| 11 | 2001232474600 |
| 12 | 25222164942650 |
| 13 | 315640538122100 |
| 14 | 3924720693484450 |
| 15 | 48514280936275240 |
| 16 | 596460638741281825 |
| 17 | 7296675024124004450 |
| 18 | 88849865885787401525 |
| 19 | 1077249149081661058800 |
[1,10,145,2120,29660,406752,5475160,72591320, 950032770,12294612660,157545928646,2001232474600, 25222164942650,315640538122100,3924720693484450, 48514280936275240,596460638741281825, 7296675024124004450,88849865885787401525, 1077249149081661058800] |