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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 2 |
| 6 | 4 |
| 7 | 13 |
| 8 | 41 |
| 9 | 152 |
| 10 | 585 |
| 11 | 2408 |
| 12 | 10398 |
| 13 | 46922 |
| 14 | 220594 |
| 15 | 1075614 |
| 16 | 5429158 |
| 17 | 28296558 |
| 18 | 152028318 |
| 19 | 840671002 |
| 20 | 4778156476 |
| 21 | 27882129540 |
| 22 | 166867893396 |
| 23 | 1023291150769 |
| 24 | 6424498576966 |
| 25 | 41262660744958 |
| 26 | 270921037479716 |
| 27 | 1817215371471834 |
| 28 | 12444490783066300 |
| 29 | 86956014104628146 |
| 30 | 619630222992962304 |
| 31 | 4500360360596423580 |
| 32 | 33298628793663193094 |
| 33 | 250878144285496830342 |
| 34 | 1923797779018220870457 |
| 35 | 15008171270194837029808 |
[1,1,1,1,1,2,4,13,41,152,585,2408,10398,46922, 220594,1075614,5429158,28296558,152028318, 840671002,4778156476,27882129540,166867893396, 1023291150769,6424498576966,41262660744958, 270921037479716,1817215371471834, 12444490783066300,86956014104628146, 619630222992962304,4500360360596423580, 33298628793663193094,250878144285496830342, 1923797779018220870457,15008171270194837029808] |