n | a(n) |
---|---|
0 | 1 |
1 | 3 |
2 | 18 |
3 | 128 |
4 | 876 |
5 | 6138 |
6 | 43373 |
7 | 307857 |
8 | 2194731 |
9 | 15698743 |
10 | 112614054 |
11 | 809905638 |
12 | 5838361138 |
13 | 42178611879 |
14 | 305340946455 |
15 | 2214760026120 |
16 | 16094665727934 |
17 | 117171115942752 |
18 | 854506665035841 |
19 | 6242259681316251 |
20 | 45674776431331398 |
[1,3,18,128,876,6138,43373,307857,2194731, 15698743,112614054,809905638,5838361138, 42178611879,305340946455,2214760026120, 16094665727934,117171115942752,854506665035841, 6242259681316251,45674776431331398] |