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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 3 |
| 5 | 6 |
| 6 | 15 |
| 7 | 41 |
| 8 | 115 |
| 9 | 345 |
| 10 | 1103 |
| 11 | 3664 |
| 12 | 12763 |
| 13 | 46415 |
| 14 | 175652 |
| 15 | 691001 |
| 16 | 2821116 |
| 17 | 11932174 |
| 18 | 52211412 |
| 19 | 236007973 |
| 20 | 1100528508 |
| 21 | 5287050500 |
| 22 | 26134330813 |
| 23 | 132760735671 |
| 24 | 692294900849 |
| 25 | 3701754158688 |
| 26 | 20275893222445 |
| 27 | 113657560920970 |
| 28 | 651449039159673 |
| 29 | 3814790900995022 |
| 30 | 22805438484189851 |
[1,1,1,3,6,15,41,115,345,1103,3664,12763,46415, 175652,691001,2821116,11932174,52211412,236007973, 1100528508,5287050500,26134330813,132760735671, 692294900849,3701754158688,20275893222445, 113657560920970,651449039159673,3814790900995022, 22805438484189851] |