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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 15 |
| 5 | 41 |
| 6 | 95 |
| 7 | 243 |
| 8 | 567 |
| 9 | 1366 |
| 10 | 3189 |
| 11 | 7532 |
| 12 | 17428 |
| 13 | 40590 |
| 14 | 93465 |
| 15 | 215331 |
| 16 | 493150 |
| 17 | 1127978 |
| 18 | 2569049 |
| 19 | 5841442 |
| 20 | 13240351 |
| 21 | 29953601 |
| 22 | 67596500 |
| 23 | 152258270 |
| 24 | 342235866 |
| 25 | 767895382 |
| 26 | 1719813753 |
| 27 | 3845442485 |
| 28 | 8584197657 |
| 29 | 19133459138 |
| 30 | 42583565928 |
| 31 | 94641591888 |
[1,2,6,15,41,95,243,567,1366,3189,7532,17428, 40590,93465,215331,493150,1127978,2569049,5841442, 13240351,29953601,67596500,152258270,342235866, 767895382,1719813753,3845442485,8584197657, 19133459138,42583565928,94641591888] |