n | a(n) |
---|---|
1 | -1 |
2 | -1 |
3 | 1 |
4 | 7 |
5 | 23 |
6 | 73 |
7 | 277 |
8 | 1355 |
9 | 8347 |
10 | 61573 |
11 | 523913 |
12 | 5024167 |
13 | 53479135 |
14 | 624890417 |
15 | 7946278813 |
16 | 109195935523 |
17 | 1612048228547 |
18 | 25439293045885 |
19 | 427278358483537 |
20 | 7609502950269503 |
21 | 143217213477235783 |
22 | 2840152418116022377 |
[-1,-1,1,7,23,73,277,1355,8347,61573,523913, 5024167,53479135,624890417,7946278813, 109195935523,1612048228547,25439293045885, 427278358483537,7609502950269503, 143217213477235783,2840152418116022377] |