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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 30 |
| 4 | 205 |
| 5 | 1525 |
| 6 | 12001 |
| 7 | 98229 |
| 8 | 827651 |
| 9 | 7130614 |
| 10 | 62528631 |
| 11 | 556247554 |
| 12 | 5007588460 |
| 13 | 45535148222 |
| 14 | 417625550140 |
| 15 | 3858724742014 |
| 16 | 35884576665516 |
| 17 | 335616614245440 |
| 18 | 3154800011439675 |
| 19 | 29789198944740050 |
| 20 | 282426795122071741 |
| 21 | 2687467779597815314 |
| 22 | 25658105671446219050 |
[1,1,5,30,205,1525,12001,98229,827651,7130614, 62528631,556247554,5007588460,45535148222, 417625550140,3858724742014,35884576665516, 335616614245440,3154800011439675, 29789198944740050,282426795122071741, 2687467779597815314,25658105671446219050] |