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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 22 |
| 5 | 129 |
| 6 | 1411 |
| 7 | 16813 |
| 8 | 266372 |
| 9 | 4787349 |
| 10 | 100391653 |
| 11 | 2357947701 |
| 12 | 61980047702 |
| 13 | 1792160394049 |
| 14 | 56707753687079 |
| 15 | 1946197516142925 |
| 16 | 72061992621375496 |
| 17 | 2862423051509815809 |
| 18 | 121441389759089405193 |
| 19 | 5480386857784802185957 |
[1,2,5,22,129,1411,16813,266372,4787349,100391653, 2357947701,61980047702,1792160394049, 56707753687079,1946197516142925,72061992621375496, 2862423051509815809,121441389759089405193, 5480386857784802185957] |