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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 10 |
| 5 | 22 |
| 6 | 76 |
| 7 | 217 |
| 8 | 750 |
| 9 | 2438 |
| 10 | 8524 |
| 11 | 29414 |
| 12 | 104468 |
| 13 | 371516 |
| 14 | 1338936 |
| 15 | 4847637 |
| 16 | 17685270 |
| 17 | 64823110 |
| 18 | 238843660 |
| 19 | 883634026 |
| 20 | 3282152588 |
| 21 | 12233141908 |
| 22 | 45741634536 |
| 23 | 171529836218 |
| 24 | 644953425740 |
| 25 | 2430973304732 |
| 26 | 9183681736376 |
[1,1,2,3,10,22,76,217,750,2438,8524,29414,104468, 371516,1338936,4847637,17685270,64823110, 238843660,883634026,3282152588,12233141908, 45741634536,171529836218,644953425740, 2430973304732,9183681736376] |