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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 2 |
| 4 | 1 |
| 5 | 3 |
| 6 | 7 |
| 7 | 31 |
| 8 | 69 |
| 9 | 31 |
| 10 | 100 |
| 11 | 231 |
| 12 | 562 |
| 13 | 3041 |
| 14 | 12726 |
| 15 | 28493 |
| 16 | 12726 |
| 17 | 41219 |
| 18 | 95164 |
| 19 | 612203 |
| 20 | 1319570 |
| 21 | 8529623 |
| 22 | 52497308 |
| 23 | 218518855 |
| 24 | 489535018 |
| 25 | 218518855 |
| 26 | 708053873 |
| 27 | 1634626601 |
| 28 | 7246560277 |
| 29 | 37867427986 |
| 30 | 82981416249 |
| 31 | 701718757978 |
[0,1,2,1,3,7,31,69,31,100,231,562,3041,12726, 28493,12726,41219,95164,612203,1319570,8529623, 52497308,218518855,489535018,218518855,708053873, 1634626601,7246560277,37867427986,82981416249, 701718757978] |