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| n | a(n) |
|---|---|
| 1 | 4 |
| 2 | 4 |
| 3 | 196 |
| 4 | 1444 |
| 5 | 18769 |
| 6 | 186624 |
| 7 | 2007889 |
| 8 | 20738916 |
| 9 | 216384100 |
| 10 | 2246191236 |
| 11 | 23336228644 |
| 12 | 242343536656 |
| 13 | 2516566604161 |
| 14 | 26133852688384 |
| 15 | 271375312681729 |
| 16 | 2818084749524496 |
| 17 | 29263464821074276 |
| 18 | 303881662686399876 |
[4,4,196,1444,18769,186624,2007889,20738916, 216384100,2246191236,23336228644,242343536656, 2516566604161,26133852688384,271375312681729, 2818084749524496,29263464821074276, 303881662686399876] |