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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 4 |
| 3 | 28 |
| 4 | 124 |
| 5 | 601 |
| 6 | 8188 |
| 7 | 131068 |
| 8 | 524284 |
| 9 | 5758678 |
| 10 | 269332797 |
| 11 | 2147483644 |
| 12 | 60499757946 |
| 13 | 322343434415 |
| 14 | 5567835897839 |
| 15 | 16557488261208 |
| 16 | 7853427629182494 |
| 17 | 426047939903614778 |
| 18 | 2305843009213693948 |
| 19 | 141920345591572240917 |
[0,4,28,124,601,8188,131068,524284,5758678, 269332797,2147483644,60499757946,322343434415, 5567835897839,16557488261208,7853427629182494, 426047939903614778,2305843009213693948, 141920345591572240917] |