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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 7 |
| 3 | 0 |
| 4 | 23 |
| 5 | 56 |
| 6 | 15 |
| 7 | 176 |
| 8 | 455 |
| 9 | 184 |
| 10 | 1295 |
| 11 | 2672 |
| 12 | 7303 |
| 13 | 3576 |
| 14 | 19407 |
| 15 | 54192 |
| 16 | 41927 |
| 17 | 214200 |
| 18 | 166159 |
| 19 | 856688 |
| 20 | 666759 |
| 21 | 3431928 |
| 22 | 2669519 |
| 23 | 13718448 |
| 24 | 10675143 |
| 25 | 55002296 |
| 26 | 42699023 |
| 27 | 219484784 |
| 28 | 171584647 |
| 29 | 877944312 |
| 30 | 716749775 |
| 31 | 3578876848 |
| 32 | 2862801863 |
| 33 | 14323893432 |
[1,2,7,0,23,56,15,176,455,184,1295,2672,7303,3576, 19407,54192,41927,214200,166159,856688,666759, 3431928,2669519,13718448,10675143,55002296, 42699023,219484784,171584647,877944312,716749775, 3578876848,2862801863,14323893432] |