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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 17 |
| 4 | 59 |
| 5 | 204 |
| 6 | 755 |
| 7 | 2886 |
| 8 | 10983 |
| 9 | 42642 |
| 10 | 169339 |
| 11 | 673729 |
| 12 | 2696817 |
| 13 | 10941944 |
| 14 | 44610497 |
| 15 | 182309217 |
| 16 | 750649555 |
| 17 | 3106888066 |
| 18 | 12882897639 |
| 19 | 53637560223 |
| 20 | 224296097237 |
| 21 | 939822049608 |
| 22 | 3947315869157 |
| 23 | 16633079275264 |
| 24 | 70233934528157 |
| 25 | 297056448537970 |
| 26 | 1259315399665313 |
| 27 | 5348993388208203 |
[1,2,5,17,59,204,755,2886,10983,42642,169339, 673729,2696817,10941944,44610497,182309217, 750649555,3106888066,12882897639,53637560223, 224296097237,939822049608,3947315869157, 16633079275264,70233934528157,297056448537970, 1259315399665313,5348993388208203] |