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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 14 |
| 5 | 33 |
| 6 | 77 |
| 7 | 174 |
| 8 | 389 |
| 9 | 860 |
| 10 | 1885 |
| 11 | 4098 |
| 12 | 8853 |
| 13 | 19020 |
| 14 | 40668 |
| 15 | 86593 |
| 16 | 183698 |
| 17 | 388421 |
| 18 | 818892 |
| 19 | 1721884 |
| 20 | 3611968 |
| 21 | 7560337 |
| 22 | 15793474 |
| 23 | 32932549 |
| 24 | 68556300 |
| 25 | 142495004 |
| 26 | 295754816 |
| 27 | 613039248 |
| 28 | 1269137729 |
| 29 | 2624393922 |
| 30 | 5421024773 |
| 31 | 11186523404 |
| 32 | 23061994524 |
[0,1,2,6,14,33,77,174,389,860,1885,4098,8853, 19020,40668,86593,183698,388421,818892,1721884, 3611968,7560337,15793474,32932549,68556300, 142495004,295754816,613039248,1269137729, 2624393922,5421024773,11186523404,23061994524] |