n | a(n) |
---|---|
0 | 1 |
1 | 5 |
2 | -15 |
3 | 45 |
4 | -135 |
5 | 405 |
6 | -1215 |
7 | 3645 |
8 | -10935 |
9 | 32805 |
10 | -98415 |
11 | 295245 |
12 | -885735 |
13 | 2657205 |
14 | -7971615 |
15 | 23914845 |
16 | -71744535 |
17 | 215233605 |
18 | -645700815 |
19 | 1937102445 |
20 | -5811307335 |
21 | 17433922005 |
22 | -52301766015 |
23 | 156905298045 |
24 | -470715894135 |
25 | 1412147682405 |
26 | -4236443047215 |
[1,5,-15,45,-135,405,-1215,3645,-10935,32805, -98415,295245,-885735,2657205,-7971615,23914845, -71744535,215233605,-645700815,1937102445, -5811307335,17433922005,-52301766015,156905298045, -470715894135,1412147682405,-4236443047215] |