n | a(n) |
---|---|
1 | 20 |
2 | 60 |
3 | 180 |
4 | 540 |
5 | 1620 |
6 | 4860 |
7 | 14580 |
8 | 43740 |
9 | 131220 |
10 | 393660 |
11 | 1180980 |
12 | 3542940 |
13 | 10628820 |
14 | 31886460 |
15 | 95659380 |
16 | 286978140 |
17 | 860934420 |
18 | 2582803260 |
19 | 7748409780 |
20 | 23245229340 |
21 | 69735688020 |
22 | 209207064060 |
23 | 627621192180 |
24 | 1882863576540 |
[20,60,180,540,1620,4860,14580,43740,131220, 393660,1180980,3542940,10628820,31886460,95659380, 286978140,860934420,2582803260,7748409780, 23245229340,69735688020,209207064060,627621192180, 1882863576540] |