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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 12 |
| 3 | 92 |
| 4 | 572 |
| 5 | 4062 |
| 6 | 29467 |
| 7 | 213225 |
| 8 | 1540686 |
| 9 | 11163495 |
| 10 | 80656708 |
| 11 | 581473349 |
| 12 | 4190483128 |
| 13 | 30199355040 |
| 14 | 217538559602 |
| 15 | 1566825952174 |
| 16 | 11283025994195 |
| 17 | 81236036737903 |
| 18 | 584831754731217 |
| 19 | 4210022381269251 |
| 20 | 30304818855812080 |
[1,12,92,572,4062,29467,213225,1540686,11163495, 80656708,581473349,4190483128,30199355040, 217538559602,1566825952174,11283025994195, 81236036737903,584831754731217,4210022381269251, 30304818855812080] |