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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 6 |
| 5 | 20 |
| 6 | 71 |
| 7 | 264 |
| 8 | 1018 |
| 9 | 4032 |
| 10 | 16305 |
| 11 | 67042 |
| 12 | 279444 |
| 13 | 1178088 |
| 14 | 5014596 |
| 15 | 21521488 |
| 16 | 93027025 |
| 17 | 404630318 |
| 18 | 1769704106 |
| 19 | 7778030834 |
| 20 | 34335337802 |
| 21 | 152168657438 |
| 22 | 676796514510 |
| 23 | 3019945599904 |
| 24 | 13515300673984 |
| 25 | 60649985907334 |
| 26 | 272847379282493 |
| 27 | 1230295797205452 |
| 28 | 5559373120441048 |
| 29 | 25171114275512520 |
| 30 | 114177375142080814 |
| 31 | 518806321789317040 |
| 32 | 2361183952087172306 |
| 33 | 10762422470020855820 |
| 34 | 49125407360603361370 |
| 35 | 224533932290057629076 |
| 36 | 1027553322543206612019 |
| 37 | 4708070541211739962738 |
| 38 | 21595828228486254332762 |
[1,1,2,6,20,71,264,1018,4032,16305,67042,279444, 1178088,5014596,21521488,93027025,404630318, 1769704106,7778030834,34335337802,152168657438, 676796514510,3019945599904,13515300673984, 60649985907334,272847379282493,1230295797205452, 5559373120441048,25171114275512520, 114177375142080814,518806321789317040, 2361183952087172306,10762422470020855820, 49125407360603361370,224533932290057629076, 1027553322543206612019,4708070541211739962738, 21595828228486254332762] |