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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 9 |
| 5 | 26 |
| 6 | 77 |
| 7 | 246 |
| 8 | 805 |
| 9 | 2702 |
| 10 | 9238 |
| 11 | 32066 |
| 12 | 112674 |
| 13 | 400024 |
| 14 | 1432736 |
| 15 | 5170584 |
| 16 | 18783763 |
| 17 | 68635478 |
| 18 | 252087092 |
| 19 | 930138522 |
| 20 | 3446163221 |
| 21 | 12815663678 |
| 22 | 47820430994 |
| 23 | 178987624514 |
| 24 | 671825076732 |
| 25 | 2528212128756 |
| 26 | 9536894864387 |
| 27 | 36054433808299 |
| 28 | 136583760727865 |
| 29 | 518401146543812 |
| 30 | 1971076359414358 |
| 31 | 7506908923471954 |
| 32 | 28634752202227978 |
[1,2,4,9,26,77,246,805,2702,9238,32066,112674, 400024,1432736,5170584,18783763,68635478, 252087092,930138522,3446163221,12815663678, 47820430994,178987624514,671825076732, 2528212128756,9536894864387,36054433808299, 136583760727865,518401146543812,1971076359414358, 7506908923471954,28634752202227978] |