n | a(n) |
---|---|
0 | 1 |
1 | 4 |
2 | 18 |
3 | 88 |
4 | 468 |
5 | 2672 |
6 | 16072 |
7 | 100064 |
8 | 636368 |
9 | 4097984 |
10 | 26579488 |
11 | 173093760 |
12 | 1129796928 |
13 | 7383588608 |
14 | 48287978624 |
15 | 315921649152 |
16 | 2067346607360 |
17 | 13530037877760 |
18 | 88555066819072 |
19 | 579620448450560 |
20 | 3793872862974976 |
21 | 24832858496561152 |
22 | 162544900186359808 |
[1,4,18,88,468,2672,16072,100064,636368,4097984, 26579488,173093760,1129796928,7383588608, 48287978624,315921649152,2067346607360, 13530037877760,88555066819072,579620448450560, 3793872862974976,24832858496561152, 162544900186359808] |