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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 11 |
| 3 | 61 |
| 4 | 451 |
| 5 | 3001 |
| 6 | 20801 |
| 7 | 141961 |
| 8 | 974611 |
| 9 | 6675901 |
| 10 | 45768251 |
| 11 | 313671601 |
| 12 | 2150012161 |
| 13 | 14736206161 |
| 14 | 101003973851 |
| 15 | 692290189501 |
| 16 | 4745031073651 |
| 17 | 32522917584361 |
| 18 | 222915417520961 |
| 19 | 1527884938291801 |
| 20 | 10472279325329251 |
| 21 | 71778069881360701 |
| 22 | 491974211042344811 |
| 23 | 3372041404278257761 |
[1,11,61,451,3001,20801,141961,974611,6675901, 45768251,313671601,2150012161,14736206161, 101003973851,692290189501,4745031073651, 32522917584361,222915417520961,1527884938291801, 10472279325329251,71778069881360701, 491974211042344811,3372041404278257761] |