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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 8 |
| 5 | 17 |
| 6 | 50 |
| 7 | 133 |
| 8 | 434 |
| 9 | 1275 |
| 10 | 4246 |
| 11 | 13515 |
| 12 | 46550 |
| 13 | 156419 |
| 14 | 555534 |
| 15 | 1951733 |
| 16 | 7092896 |
| 17 | 25736111 |
| 18 | 95429785 |
| 19 | 354788330 |
| 20 | 1338863594 |
| 21 | 5077947025 |
| 22 | 19463581574 |
| 23 | 75041004927 |
| 24 | 291655368276 |
| 25 | 1139929297661 |
| 26 | 4484645500788 |
| 27 | 17733661901866 |
| 28 | 70514235062726 |
| 29 | 281674503226354 |
| 30 | 1130639774956010 |
| 31 | 4557063998438378 |
[1,1,2,3,8,17,50,133,434,1275,4246,13515,46550, 156419,555534,1951733,7092896,25736111,95429785, 354788330,1338863594,5077947025,19463581574, 75041004927,291655368276,1139929297661, 4484645500788,17733661901866,70514235062726, 281674503226354,1130639774956010,4557063998438378] |