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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 7 |
| 5 | 15 |
| 6 | 32 |
| 7 | 52 |
| 8 | 126 |
| 9 | 225 |
| 10 | 554 |
| 11 | 995 |
| 12 | 2446 |
| 13 | 5386 |
| 14 | 11808 |
| 15 | 19869 |
| 16 | 49025 |
| 17 | 109837 |
| 18 | 245854 |
| 19 | 425227 |
| 20 | 1064505 |
| 21 | 2413233 |
| 22 | 5466912 |
| 23 | 9592348 |
| 24 | 24178488 |
| 25 | 45073812 |
| 26 | 113262740 |
| 27 | 208166868 |
| 28 | 518091370 |
| 29 | 1155428876 |
| 30 | 2571714336 |
| 31 | 4419410606 |
| 32 | 11038230966 |
| 33 | 20406919817 |
[1,1,2,3,7,15,32,52,126,225,554,995,2446,5386, 11808,19869,49025,109837,245854,425227,1064505, 2413233,5466912,9592348,24178488,45073812, 113262740,208166868,518091370,1155428876, 2571714336,4419410606,11038230966,20406919817] |