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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 17 |
| 4 | 110 |
| 5 | 783 |
| 6 | 5908 |
| 7 | 46433 |
| 8 | 376029 |
| 9 | 3115941 |
| 10 | 26293410 |
| 11 | 225166050 |
| 12 | 1951877304 |
| 13 | 17094430060 |
| 14 | 151026790086 |
| 15 | 1344405191931 |
| 16 | 12046557221374 |
| 17 | 108569555036541 |
| 18 | 983512740523989 |
| 19 | 8950335155129326 |
| 20 | 81786796816686222 |
| 21 | 750133309106091800 |
| 22 | 6903286130025559800 |
| 23 | 63724450582843480092 |
| 24 | 589897018021520290940 |
| 25 | 5474784437150040712036 |
| 26 | 50932035767512193052753 |
| 27 | 474865449870890392910894 |
[1,1,3,17,110,783,5908,46433,376029,3115941, 26293410,225166050,1951877304,17094430060, 151026790086,1344405191931,12046557221374, 108569555036541,983512740523989,8950335155129326, 81786796816686222,750133309106091800, 6903286130025559800,63724450582843480092, 589897018021520290940,5474784437150040712036, 50932035767512193052753,474865449870890392910894] |