n | a(n) |
---|---|
1 | 2 |
2 | 6 |
3 | 18 |
4 | 51 |
5 | 142 |
6 | 405 |
7 | 1157 |
8 | 3289 |
9 | 9344 |
10 | 26580 |
11 | 75621 |
12 | 215076 |
13 | 611683 |
14 | 1739781 |
15 | 4948421 |
16 | 14074414 |
17 | 40030688 |
18 | 113856507 |
19 | 323834334 |
20 | 921058929 |
21 | 2619701953 |
22 | 7451032833 |
23 | 21192445976 |
24 | 60276171664 |
25 | 171439240421 |
26 | 487612482144 |
[2,6,18,51,142,405,1157,3289,9344,26580,75621, 215076,611683,1739781,4948421,14074414,40030688, 113856507,323834334,921058929,2619701953, 7451032833,21192445976,60276171664,171439240421, 487612482144] |