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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 22 |
| 5 | 103 |
| 6 | 614 |
| 7 | 3872 |
| 8 | 26414 |
| 9 | 186988 |
| 10 | 1367976 |
| 11 | 10254326 |
| 12 | 78461338 |
| 13 | 610598818 |
| 14 | 4821248244 |
| 15 | 38546510368 |
| 16 | 311560875422 |
| 17 | 2542507084588 |
| 18 | 20925300483992 |
| 19 | 173530381632724 |
| 20 | 1448900079476152 |
| 21 | 12172334379246523 |
| 22 | 102833593763830038 |
| 23 | 873187910184763024 |
| 24 | 7449120536014301138 |
[1,1,2,6,22,103,614,3872,26414,186988,1367976, 10254326,78461338,610598818,4821248244, 38546510368,311560875422,2542507084588, 20925300483992,173530381632724,1448900079476152, 12172334379246523,102833593763830038, 873187910184763024,7449120536014301138] |