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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 8 |
| 5 | 19 |
| 6 | 44 |
| 7 | 84 |
| 8 | 212 |
| 9 | 474 |
| 10 | 1008 |
| 11 | 2438 |
| 12 | 5436 |
| 13 | 12045 |
| 14 | 28174 |
| 15 | 63292 |
| 16 | 142936 |
| 17 | 330285 |
| 18 | 748286 |
| 19 | 1707460 |
| 20 | 3930660 |
| 21 | 8968641 |
| 22 | 20569786 |
| 23 | 47335822 |
| 24 | 108517496 |
| 25 | 249608726 |
| 26 | 574843912 |
| 27 | 1322068800 |
| 28 | 3046723144 |
| 29 | 7024972918 |
| 30 | 16192943826 |
| 31 | 37371650024 |
[1,2,6,8,19,44,84,212,474,1008,2438,5436,12045, 28174,63292,142936,330285,748286,1707460,3930660, 8968641,20569786,47335822,108517496,249608726, 574843912,1322068800,3046723144,7024972918, 16192943826,37371650024] |