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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 5 |
| 4 | 12 |
| 5 | 21 |
| 6 | 60 |
| 7 | 145 |
| 8 | 461 |
| 9 | 1455 |
| 10 | 4920 |
| 11 | 16825 |
| 12 | 58937 |
| 13 | 208049 |
| 14 | 743218 |
| 15 | 2674539 |
| 16 | 9695792 |
| 17 | 35357723 |
| 18 | 129647876 |
| 19 | 477638761 |
| 20 | 1767273109 |
| 21 | 6564120913 |
| 22 | 24466300714 |
| 23 | 91482563719 |
| 24 | 343059732922 |
| 25 | 1289904147511 |
| 26 | 4861946817610 |
[1,3,5,12,21,60,145,461,1455,4920,16825,58937, 208049,743218,2674539,9695792,35357723,129647876, 477638761,1767273109,6564120913,24466300714, 91482563719,343059732922,1289904147511, 4861946817610] |