n | a(n) |
---|---|
0 | 1 |
1 | 0 |
2 | -1 |
3 | -1 |
4 | -2 |
5 | -4 |
6 | -9 |
7 | -21 |
8 | -51 |
9 | -127 |
10 | -323 |
11 | -835 |
12 | -2188 |
13 | -5798 |
14 | -15511 |
15 | -41835 |
16 | -113634 |
17 | -310572 |
18 | -853467 |
19 | -2356779 |
20 | -6536382 |
21 | -18199284 |
22 | -50852019 |
23 | -142547559 |
24 | -400763223 |
25 | -1129760415 |
26 | -3192727797 |
27 | -9043402501 |
28 | -25669818476 |
[1,0,-1,-1,-2,-4,-9,-21,-51,-127,-323,-835,-2188, -5798,-15511,-41835,-113634,-310572,-853467, -2356779,-6536382,-18199284,-50852019,-142547559, -400763223,-1129760415,-3192727797,-9043402501, -25669818476] |