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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 7 |
| 5 | 22 |
| 6 | 65 |
| 7 | 213 |
| 8 | 693 |
| 9 | 2352 |
| 10 | 8034 |
| 11 | 28014 |
| 12 | 98505 |
| 13 | 350548 |
| 14 | 1256827 |
| 15 | 4542395 |
| 16 | 16517631 |
| 17 | 60417708 |
| 18 | 222087320 |
| 19 | 820099720 |
| 20 | 3040555978 |
| 21 | 11314532376 |
| 22 | 42243332130 |
| 23 | 158196980682 |
| 24 | 594075563613 |
| 25 | 2236627194858 |
| 26 | 8440468925400 |
[1,1,3,7,22,65,213,693,2352,8034,28014,98505, 350548,1256827,4542395,16517631,60417708, 222087320,820099720,3040555978,11314532376, 42243332130,158196980682,594075563613, 2236627194858,8440468925400] |