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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 14 |
| 5 | 42 |
| 6 | 165 |
| 7 | 714 |
| 8 | 3094 |
| 9 | 14858 |
| 10 | 79534 |
| 11 | 447051 |
| 12 | 2714690 |
| 13 | 17395070 |
| 14 | 114371070 |
| 15 | 783152070 |
| 16 | 5708587335 |
| 17 | 43848093003 |
| 18 | 342444658094 |
| 19 | 2803119896185 |
| 20 | 23619540863730 |
| 21 | 201813981102615 |
| 22 | 1793779293633437 |
| 23 | 16342050964565645 |
| 24 | 154170926013430326 |
| 25 | 1518409177581024365 |
[1,2,5,14,42,165,714,3094,14858,79534,447051, 2714690,17395070,114371070,783152070,5708587335, 43848093003,342444658094,2803119896185, 23619540863730,201813981102615,1793779293633437, 16342050964565645,154170926013430326, 1518409177581024365] |