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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 17 |
| 5 | 66 |
| 6 | 295 |
| 7 | 1408 |
| 8 | 7103 |
| 9 | 37140 |
| 10 | 199915 |
| 11 | 1100752 |
| 12 | 6174851 |
| 13 | 35179360 |
| 14 | 203069441 |
| 15 | 1185443261 |
| 16 | 6987897811 |
| 17 | 41544411702 |
| 18 | 248853224179 |
| 19 | 1500635461876 |
| 20 | 9103375030686 |
| 21 | 55521964829070 |
| 22 | 340282330969943 |
| 23 | 2094756627157200 |
[1,2,5,17,66,295,1408,7103,37140,199915,1100752, 6174851,35179360,203069441,1185443261,6987897811, 41544411702,248853224179,1500635461876, 9103375030686,55521964829070,340282330969943, 2094756627157200] |