n | a(n) |
---|---|
1 | 4 |
2 | 8 |
3 | 18 |
4 | 126 |
5 | 380 |
6 | 4112 |
7 | 14310 |
8 | 184410 |
9 | 9272780 |
10 | 34669602 |
11 | 1857545300 |
12 | 26818405352 |
13 | 102282248574 |
14 | 1497215711538 |
15 | 84973644983780 |
16 | 4885261149611790 |
17 | 18900353608280300 |
18 | 1101298162244236182 |
19 | 16628051030379615882 |
[4,8,18,126,380,4112,14310,184410,9272780, 34669602,1857545300,26818405352,102282248574, 1497215711538,84973644983780,4885261149611790, 18900353608280300,1101298162244236182, 16628051030379615882] |