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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 1 |
| 4 | 2 |
| 5 | 4 |
| 6 | 14 |
| 7 | 74 |
| 8 | 494 |
| 9 | 3854 |
| 10 | 34094 |
| 11 | 336494 |
| 12 | 3662894 |
| 13 | 43579694 |
| 14 | 562498094 |
| 15 | 7827355694 |
| 16 | 116800219694 |
| 17 | 1860366043694 |
| 18 | 31500985051694 |
| 19 | 565032127195694 |
| 20 | 10702123827931694 |
| 21 | 213443957842651694 |
| 22 | 4471022472151771694 |
| 23 | 98137749786952411694 |
| 24 | 2252472478027367131694 |
[1,2,1,2,4,14,74,494,3854,34094,336494,3662894, 43579694,562498094,7827355694,116800219694, 1860366043694,31500985051694,565032127195694, 10702123827931694,213443957842651694, 4471022472151771694,98137749786952411694, 2252472478027367131694] |