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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 14 |
| 5 | 44 |
| 6 | 147 |
| 7 | 505 |
| 8 | 1750 |
| 9 | 6065 |
| 10 | 20950 |
| 11 | 72052 |
| 12 | 246715 |
| 13 | 841345 |
| 14 | 2858714 |
| 15 | 9682221 |
| 16 | 32700942 |
| 17 | 110173948 |
| 18 | 370393059 |
| 19 | 1242869721 |
| 20 | 4163561358 |
| 21 | 13927246329 |
| 22 | 46526402422 |
| 23 | 155249799428 |
| 24 | 517505902283 |
| 25 | 1723457914689 |
| 26 | 5734951039346 |
[1,2,5,14,44,147,505,1750,6065,20950,72052,246715, 841345,2858714,9682221,32700942,110173948, 370393059,1242869721,4163561358,13927246329, 46526402422,155249799428,517505902283, 1723457914689,5734951039346] |