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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 8 |
| 3 | 46 |
| 4 | 338 |
| 5 | 2996 |
| 6 | 30952 |
| 7 | 364148 |
| 8 | 4797116 |
| 9 | 69854968 |
| 10 | 1113018176 |
| 11 | 19244304872 |
| 12 | 358608737368 |
| 13 | 7160626365296 |
| 14 | 152458303437728 |
| 15 | 3446434090192816 |
| 16 | 82412163484132112 |
| 17 | 2077739630757428768 |
| 18 | 55068742629150564736 |
| 19 | 1530394053934299827168 |
| 20 | 44490672191650220419616 |
[1,2,8,46,338,2996,30952,364148,4797116,69854968, 1113018176,19244304872,358608737368,7160626365296, 152458303437728,3446434090192816, 82412163484132112,2077739630757428768, 55068742629150564736,1530394053934299827168, 44490672191650220419616] |