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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 2 |
| 5 | 5 |
| 6 | 5 |
| 7 | 15 |
| 8 | 17 |
| 9 | 78 |
| 10 | 102 |
| 11 | 569 |
| 12 | 919 |
| 13 | 6142 |
| 14 | 11170 |
| 15 | 86043 |
| 16 | 174957 |
| 17 | 1495234 |
| 18 | 3338570 |
| 19 | 31029867 |
| 20 | 74669371 |
| 21 | 740854138 |
| 22 | 1885642110 |
| 23 | 19616697093 |
| 24 | 51936661281 |
| 25 | 558093960576 |
| 26 | 1517106442790 |
| 27 | 16655034027581 |
| 28 | 46067262638225 |
[1,1,2,2,5,5,15,17,78,102,569,919,6142,11170, 86043,174957,1495234,3338570,31029867,74669371, 740854138,1885642110,19616697093,51936661281, 558093960576,1517106442790,16655034027581, 46067262638225] |