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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 1 |
| 3 | 3 |
| 4 | 8 |
| 5 | 25 |
| 6 | 99 |
| 7 | 476 |
| 8 | 2643 |
| 9 | 16575 |
| 10 | 116002 |
| 11 | 895719 |
| 12 | 7554311 |
| 13 | 69051034 |
| 14 | 679913073 |
| 15 | 7174562327 |
| 16 | 80765185416 |
| 17 | 966076987581 |
| 18 | 12235992073975 |
| 19 | 163590477924708 |
| 20 | 2302288709067167 |
| 21 | 34021599945907915 |
| 22 | 526690307104399482 |
| 23 | 8524372522971447683 |
| 24 | 143963947160570293851 |
[0,0,1,3,8,25,99,476,2643,16575,116002,895719, 7554311,69051034,679913073,7174562327,80765185416, 966076987581,12235992073975,163590477924708, 2302288709067167,34021599945907915, 526690307104399482,8524372522971447683, 143963947160570293851] |