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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 7 |
| 4 | 29 |
| 5 | 141 |
| 6 | 832 |
| 7 | 5729 |
| 8 | 45217 |
| 9 | 402359 |
| 10 | 3985942 |
| 11 | 43500339 |
| 12 | 518515997 |
| 13 | 6702036193 |
| 14 | 93361811396 |
| 15 | 1394334141349 |
| 16 | 22223762217953 |
| 17 | 376516856157771 |
| 18 | 6756666799667818 |
| 19 | 128025250352208551 |
| 20 | 2554170591729180733 |
| 21 | 53517087513085077221 |
| 22 | 1174963644698963576488 |
[1,1,2,7,29,141,832,5729,45217,402359,3985942, 43500339,518515997,6702036193,93361811396, 1394334141349,22223762217953,376516856157771, 6756666799667818,128025250352208551, 2554170591729180733,53517087513085077221, 1174963644698963576488] |