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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 16 |
| 4 | 97 |
| 5 | 645 |
| 6 | 4539 |
| 7 | 33242 |
| 8 | 250715 |
| 9 | 1934131 |
| 10 | 15190377 |
| 11 | 121050779 |
| 12 | 976334857 |
| 13 | 7954909796 |
| 14 | 65378035310 |
| 15 | 541346845867 |
| 16 | 4511820592102 |
| 17 | 37819912868231 |
| 18 | 318639423484669 |
| 19 | 2696819879180630 |
| 20 | 22918021992024063 |
| 21 | 195480539889732302 |
| 22 | 1672951468057552136 |
| 23 | 14361120982757852887 |
| 24 | 123625070638172667688 |
| 25 | 1066939084577136857174 |
[1,1,3,16,97,645,4539,33242,250715,1934131, 15190377,121050779,976334857,7954909796, 65378035310,541346845867,4511820592102, 37819912868231,318639423484669,2696819879180630, 22918021992024063,195480539889732302, 1672951468057552136,14361120982757852887, 123625070638172667688,1066939084577136857174] |