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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 4 |
| 3 | 48 |
| 4 | 466 |
| 5 | 5101 |
| 6 | 74685 |
| 7 | 1276034 |
| 8 | 30242236 |
| 9 | 1056423010 |
| 10 | 50039513246 |
| 11 | 3406811335705 |
| 12 | 353276120560238 |
| 13 | 52792202092264104 |
[0,4,48,466,5101,74685,1276034,30242236, 1056423010,50039513246,3406811335705, 353276120560238,52792202092264104] |