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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 2 |
| 3 | 3 |
| 4 | 4 |
| 5 | 54 |
| 6 | 6391 |
| 7 | 721719 |
| 8 | 73719014 |
| 9 | 819008271 |
| 10 | 900826453 |
| 11 | 982644636 |
| 12 | 1064462818 |
| 13 | 1146281001 |
| 14 | 1228099183 |
| 15 | 1309917366 |
| 16 | 1391735548 |
| 17 | 1473553731 |
| 18 | 1555371913 |
| 19 | 1637190096 |
| 20 | 1719008278 |
| 21 | 1800826461 |
| 22 | 1882644643 |
| 23 | 1964462826 |
[2,2,3,4,54,6391,721719,73719014,819008271, 900826453,982644636,1064462818,1146281001, 1228099183,1309917366,1391735548,1473553731, 1555371913,1637190096,1719008278,1800826461, 1882644643,1964462826] |