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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 8 |
| 4 | 18 |
| 5 | 40 |
| 6 | 89 |
| 7 | 197 |
| 8 | 435 |
| 9 | 960 |
| 10 | 2118 |
| 11 | 4672 |
| 12 | 10305 |
| 13 | 22729 |
| 14 | 50131 |
| 15 | 110568 |
| 16 | 243866 |
| 17 | 537864 |
| 18 | 1186297 |
| 19 | 2616461 |
| 20 | 5770787 |
| 21 | 12727872 |
| 22 | 28072206 |
| 23 | 61915200 |
| 24 | 136558273 |
| 25 | 301188753 |
| 26 | 664292707 |
| 27 | 1465143688 |
| 28 | 3231476130 |
| 29 | 7127244968 |
| 30 | 15719633625 |
| 31 | 34670743381 |
| 32 | 76468731731 |
[1,3,8,18,40,89,197,435,960,2118,4672,10305,22729, 50131,110568,243866,537864,1186297,2616461, 5770787,12727872,28072206,61915200,136558273, 301188753,664292707,1465143688,3231476130, 7127244968,15719633625,34670743381,76468731731] |