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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 42 |
| 2 | 1911 |
| 3 | 89180 |
| 4 | 4213755 |
| 5 | 200574738 |
| 6 | 9594158301 |
| 7 | 460519598448 |
| 8 | 22162505675310 |
| 9 | 1068725273676060 |
| 10 | 51619430718553698 |
| 11 | 2496503376570051576 |
| 12 | 120872371815599997138 |
| 13 | 5857661095679076784380 |
| 14 | 284096563140435224042430 |
| 15 | 13788153197749122873525936 |
[1,42,1911,89180,4213755,200574738,9594158301, 460519598448,22162505675310,1068725273676060, 51619430718553698,2496503376570051576, 120872371815599997138,5857661095679076784380, 284096563140435224042430, 13788153197749122873525936] |