n | a(n) |
---|---|
0 | 0 |
1 | 0 |
2 | 4 |
3 | 20 |
4 | 85 |
5 | 344 |
6 | 1365 |
7 | 5368 |
8 | 21021 |
9 | 82160 |
10 | 320892 |
11 | 1253240 |
12 | 4896034 |
13 | 19137104 |
14 | 74847175 |
15 | 292929840 |
16 | 1147223325 |
17 | 4496006880 |
18 | 17631691440 |
19 | 69189377400 |
20 | 271676550390 |
21 | 1067383059600 |
22 | 4195964793930 |
23 | 16503454480656 |
24 | 64943823784050 |
25 | 255687666536224 |
[0,0,4,20,85,344,1365,5368,21021,82160,320892, 1253240,4896034,19137104,74847175,292929840, 1147223325,4496006880,17631691440,69189377400, 271676550390,1067383059600,4195964793930, 16503454480656,64943823784050,255687666536224] |