n | a(n) |
---|---|
0 | 1 |
1 | 4 |
2 | 20 |
3 | 96 |
4 | 444 |
5 | 2000 |
6 | 8840 |
7 | 38528 |
8 | 166124 |
9 | 710256 |
10 | 3016056 |
11 | 12736064 |
12 | 53530840 |
13 | 224107936 |
14 | 935062544 |
15 | 3890018816 |
16 | 16141765964 |
17 | 66829954736 |
18 | 276135664664 |
19 | 1138932645056 |
20 | 4690042582664 |
21 | 19285299964256 |
22 | 79196366286704 |
23 | 324835930747136 |
24 | 1330905207444344 |
[1,4,20,96,444,2000,8840,38528,166124,710256, 3016056,12736064,53530840,224107936,935062544, 3890018816,16141765964,66829954736,276135664664, 1138932645056,4690042582664,19285299964256, 79196366286704,324835930747136,1330905207444344] |