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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 15 |
| 5 | 45 |
| 6 | 140 |
| 7 | 448 |
| 8 | 1483 |
| 9 | 5027 |
| 10 | 17311 |
| 11 | 60469 |
| 12 | 213678 |
| 13 | 762284 |
| 14 | 2741864 |
| 15 | 9932346 |
| 16 | 36202666 |
| 17 | 132677658 |
| 18 | 488605698 |
| 19 | 1807176452 |
| 20 | 6710206574 |
| 21 | 25003642942 |
| 22 | 93468147306 |
| 23 | 350425771854 |
| 24 | 1317330452697 |
| 25 | 4964398631867 |
| 26 | 18751217069083 |
| 27 | 70975750129731 |
| 28 | 269180061675328 |
| 29 | 1022750160098864 |
| 30 | 3892577330120307 |
| 31 | 14838784128136803 |
| 32 | 56651259287153670 |
| 33 | 216586672901518164 |
| 34 | 829142137823283601 |
| 35 | 3178107527615273349 |
[1,1,2,6,15,45,140,448,1483,5027,17311,60469, 213678,762284,2741864,9932346,36202666,132677658, 488605698,1807176452,6710206574,25003642942, 93468147306,350425771854,1317330452697, 4964398631867,18751217069083,70975750129731, 269180061675328,1022750160098864,3892577330120307, 14838784128136803,56651259287153670, 216586672901518164,829142137823283601, 3178107527615273349] |