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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 8 |
| 3 | 30 |
| 4 | 126 |
| 5 | 539 |
| 6 | 2358 |
| 7 | 10526 |
| 8 | 47621 |
| 9 | 217182 |
| 10 | 1002081 |
| 11 | 4644109 |
| 12 | 21682588 |
| 13 | 101701604 |
| 14 | 478985355 |
| 15 | 2265535437 |
| 16 | 10747214934 |
| 17 | 51142755153 |
| 18 | 244020287947 |
| 19 | 1166918590405 |
| 20 | 5593066651598 |
| 21 | 26857013016864 |
| 22 | 129196968427815 |
| 23 | 622526449929799 |
| 24 | 3003950035203570 |
| 25 | 14515880870236575 |
| 26 | 70231930830344139 |
[1,2,8,30,126,539,2358,10526,47621,217182,1002081, 4644109,21682588,101701604,478985355,2265535437, 10747214934,51142755153,244020287947, 1166918590405,5593066651598,26857013016864, 129196968427815,622526449929799,3003950035203570, 14515880870236575,70231930830344139] |