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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 13 |
| 4 | 75 |
| 5 | 517 |
| 6 | 4443 |
| 7 | 43093 |
| 8 | 486315 |
| 9 | 6082117 |
| 10 | 81407163 |
| 11 | 1184034613 |
| 12 | 19251200715 |
| 13 | 342825926437 |
| 14 | 6604284459483 |
| 15 | 136398242877973 |
| 16 | 2984396941441515 |
| 17 | 68215762130020357 |
| 18 | 1627134074774283003 |
| 19 | 40749275946991321333 |
| 20 | 1079215210446044648715 |
| 21 | 30311064871950344936677 |
| 22 | 897713839789350372765723 |
[1,3,13,75,517,4443,43093,486315,6082117,81407163, 1184034613,19251200715,342825926437,6604284459483, 136398242877973,2984396941441515, 68215762130020357,1627134074774283003, 40749275946991321333,1079215210446044648715, 30311064871950344936677,897713839789350372765723] |