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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 14 |
| 5 | 39 |
| 6 | 126 |
| 7 | 396 |
| 8 | 1362 |
| 9 | 4639 |
| 10 | 16619 |
| 11 | 59519 |
| 12 | 220100 |
| 13 | 815414 |
| 14 | 3090682 |
| 15 | 11738378 |
| 16 | 45353386 |
| 17 | 175598040 |
| 18 | 688854841 |
| 19 | 2708282490 |
| 20 | 10756657528 |
| 21 | 42820338694 |
| 22 | 171830989992 |
| 23 | 691099456497 |
| 24 | 2797481451289 |
| 25 | 11348882879661 |
| 26 | 46281865516679 |
| 27 | 189139996758076 |
| 28 | 776311395758161 |
| 29 | 3192648976527350 |
[1,1,2,5,14,39,126,396,1362,4639,16619,59519, 220100,815414,3090682,11738378,45353386,175598040, 688854841,2708282490,10756657528,42820338694, 171830989992,691099456497,2797481451289, 11348882879661,46281865516679,189139996758076, 776311395758161,3192648976527350] |