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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 12 |
| 5 | 25 |
| 6 | 77 |
| 7 | 181 |
| 8 | 696 |
| 9 | 1809 |
| 10 | 5991 |
| 11 | 17609 |
| 12 | 63958 |
| 13 | 188683 |
| 14 | 653258 |
| 15 | 2112627 |
| 16 | 7535840 |
| 17 | 23721089 |
| 18 | 85713509 |
| 19 | 286499693 |
| 20 | 1026150382 |
| 21 | 3374608955 |
| 22 | 12502467560 |
| 23 | 42456829669 |
| 24 | 153777339420 |
| 25 | 523923695731 |
| 26 | 1958207627323 |
| 27 | 6732073221545 |
| 28 | 24744903814780 |
| 29 | 86428974845565 |
| 30 | 323611236508025 |
| 31 | 1126150114881781 |
[1,1,2,3,12,25,77,181,696,1809,5991,17609,63958, 188683,653258,2112627,7535840,23721089,85713509, 286499693,1026150382,3374608955,12502467560, 42456829669,153777339420,523923695731, 1958207627323,6732073221545,24744903814780, 86428974845565,323611236508025,1126150114881781] |