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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 22 |
| 4 | 72 |
| 5 | 258 |
| 6 | 949 |
| 7 | 3403 |
| 8 | 12241 |
| 9 | 44192 |
| 10 | 159272 |
| 11 | 573952 |
| 12 | 2069009 |
| 13 | 7457849 |
| 14 | 26881189 |
| 15 | 96893542 |
| 16 | 349253376 |
| 17 | 1258880466 |
| 18 | 4537629845 |
| 19 | 16355874451 |
| 20 | 58954682593 |
| 21 | 212501925632 |
| 22 | 765962408016 |
| 23 | 2760908604224 |
| 24 | 9951684619105 |
[1,5,22,72,258,949,3403,12241,44192,159272,573952, 2069009,7457849,26881189,96893542,349253376, 1258880466,4537629845,16355874451,58954682593, 212501925632,765962408016,2760908604224, 9951684619105] |