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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 15 |
| 5 | 39 |
| 6 | 127 |
| 7 | 405 |
| 8 | 1330 |
| 9 | 4478 |
| 10 | 15574 |
| 11 | 54337 |
| 12 | 194625 |
| 13 | 699722 |
| 14 | 2558633 |
| 15 | 9423633 |
| 16 | 35049948 |
| 17 | 131371020 |
| 18 | 495572962 |
| 19 | 1882605608 |
| 20 | 7196722963 |
| 21 | 27626157357 |
| 22 | 106690061753 |
| 23 | 413630954817 |
| 24 | 1610691764954 |
| 25 | 6298169581271 |
| 26 | 24703968025232 |
| 27 | 97266195844071 |
| 28 | 384155216430075 |
| 29 | 1521472349416453 |
| 30 | 6044403219103030 |
[1,1,2,5,15,39,127,405,1330,4478,15574,54337, 194625,699722,2558633,9423633,35049948,131371020, 495572962,1882605608,7196722963,27626157357, 106690061753,413630954817,1610691764954, 6298169581271,24703968025232,97266195844071, 384155216430075,1521472349416453,6044403219103030] |