n | a(n) |
---|---|
0 | 0 |
1 | 2 |
2 | 2 |
3 | 6 |
4 | 12 |
5 | 30 |
6 | 72 |
7 | 182 |
8 | 464 |
9 | 1206 |
10 | 3170 |
11 | 8426 |
12 | 22596 |
13 | 61074 |
14 | 166194 |
15 | 454950 |
16 | 1251984 |
17 | 3461574 |
18 | 9611190 |
19 | 26787378 |
20 | 74916660 |
21 | 210178458 |
22 | 591347988 |
23 | 1668172842 |
24 | 4717282752 |
25 | 13369522250 |
26 | 37970114702 |
27 | 108045430902 |
[0,2,2,6,12,30,72,182,464,1206,3170,8426,22596, 61074,166194,454950,1251984,3461574,9611190, 26787378,74916660,210178458,591347988,1668172842, 4717282752,13369522250,37970114702,108045430902] |