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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 16 |
| 5 | 52 |
| 6 | 183 |
| 7 | 664 |
| 8 | 2449 |
| 9 | 9362 |
| 10 | 36633 |
| 11 | 145270 |
| 12 | 586439 |
| 13 | 2398743 |
| 14 | 9905045 |
| 15 | 41348528 |
| 16 | 174110004 |
| 17 | 738361192 |
| 18 | 3154440182 |
| 19 | 13559465468 |
| 20 | 58601967026 |
| 21 | 254620276210 |
| 22 | 1111404780914 |
| 23 | 4871741807378 |
| 24 | 21440930894794 |
| 25 | 94702771111481 |
| 26 | 419700986590893 |
| 27 | 1865899431263205 |
| 28 | 8319362447227408 |
[1,1,2,5,16,52,183,664,2449,9362,36633,145270, 586439,2398743,9905045,41348528,174110004, 738361192,3154440182,13559465468,58601967026, 254620276210,1111404780914,4871741807378, 21440930894794,94702771111481,419700986590893, 1865899431263205,8319362447227408] |