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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 11 |
| 4 | 74 |
| 5 | 602 |
| 6 | 5452 |
| 7 | 53559 |
| 8 | 558602 |
| 9 | 6106034 |
| 10 | 69298580 |
| 11 | 811086718 |
| 12 | 9740402476 |
| 13 | 119550632788 |
| 14 | 1495039156600 |
| 15 | 19002275811887 |
| 16 | 244983878813514 |
| 17 | 3198363309664658 |
| 18 | 42225545561470084 |
| 19 | 563083734161627910 |
| 20 | 7576864105285884420 |
| 21 | 102790882283750139060 |
| 22 | 1404908982711268821720 |
[1,2,11,74,602,5452,53559,558602,6106034,69298580, 811086718,9740402476,119550632788,1495039156600, 19002275811887,244983878813514,3198363309664658, 42225545561470084,563083734161627910, 7576864105285884420,102790882283750139060, 1404908982711268821720] |