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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 7 |
| 4 | 138 |
| 5 | 5477 |
| 6 | 367640 |
| 7 | 37541883 |
| 8 | 5432772352 |
| 9 | 1059075055273 |
| 10 | 267757626501504 |
| 11 | 85244466165571535 |
| 12 | 33379687015338236672 |
| 13 | 15770655073870516443597 |
| 14 | 8847780392111931116474368 |
| 15 | 5815426547948880787678282627 |
| 16 | 4426738320076692932937846865920 |
| 17 | 3863757059392099045703984747480273 |
[1,1,7,138,5477,367640,37541883,5432772352, 1059075055273,267757626501504,85244466165571535, 33379687015338236672,15770655073870516443597, 8847780392111931116474368, 5815426547948880787678282627, 4426738320076692932937846865920, 3863757059392099045703984747480273] |