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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 11 |
| 5 | 29 |
| 6 | 91 |
| 7 | 299 |
| 8 | 1057 |
| 9 | 3884 |
| 10 | 14883 |
| 11 | 58508 |
| 12 | 235771 |
| 13 | 967790 |
| 14 | 4037807 |
| 15 | 17074475 |
| 16 | 73058753 |
| 17 | 315803342 |
| 18 | 1377445726 |
| 19 | 6056134719 |
| 20 | 26817483095 |
| 21 | 119516734167 |
| 22 | 535751271345 |
| 23 | 2414304071965 |
| 24 | 10932421750492 |
| 25 | 49723583969029 |
| 26 | 227079111492652 |
| 27 | 1040939109111200 |
| 28 | 4788357522831785 |
[1,1,2,4,11,29,91,299,1057,3884,14883,58508, 235771,967790,4037807,17074475,73058753,315803342, 1377445726,6056134719,26817483095,119516734167, 535751271345,2414304071965,10932421750492, 49723583969029,227079111492652,1040939109111200, 4788357522831785] |