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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 16 |
| 2 | 65535 |
| 3 | 21523360 |
| 4 | 1431655765 |
| 5 | 38146972656 |
| 6 | 564221981491 |
| 7 | 5538821761600 |
| 8 | 40210710958665 |
| 9 | 231627523606480 |
| 10 | 1111111111111111 |
| 11 | 4594972986357216 |
| 12 | 16807659899548765 |
| 13 | 55451384098598320 |
| 14 | 167534872139182395 |
| 15 | 469172025408063616 |
| 16 | 1229782938247303441 |
[1,16,65535,21523360,1431655765,38146972656, 564221981491,5538821761600,40210710958665, 231627523606480,1111111111111111,4594972986357216, 16807659899548765,55451384098598320, 167534872139182395,469172025408063616, 1229782938247303441] |