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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 8 |
| 4 | 21 |
| 5 | 110 |
| 6 | 343 |
| 7 | 1940 |
| 8 | 6121 |
| 9 | 34778 |
| 10 | 549007 |
| 11 | 1895276 |
| 12 | 26053093 |
| 13 | 191633234 |
| 14 | 625127671 |
| 15 | 3596342744 |
| 16 | 56912633917 |
| 17 | 1013634659958 |
| 18 | 3518365441919 |
| 19 | 48463935654772 |
| 20 | 356525456824901 |
| 21 | 1163040989874294 |
| 22 | 15635375014550515 |
| 23 | 114830228109306012 |
| 24 | 1894809644114020201 |
[1,3,8,21,110,343,1940,6121,34778,549007,1895276, 26053093,191633234,625127671,3596342744, 56912633917,1013634659958,3518365441919, 48463935654772,356525456824901,1163040989874294, 15635375014550515,114830228109306012, 1894809644114020201] |