n | a(n) |
---|---|
3 | 1 |
4 | 4 |
5 | 17 |
6 | 80 |
7 | 403 |
8 | 2128 |
9 | 11628 |
10 | 65208 |
11 | 373175 |
12 | 2170740 |
13 | 12797265 |
14 | 76292736 |
15 | 459162452 |
16 | 2786017120 |
17 | 17024247304 |
18 | 104673837384 |
19 | 647113502847 |
20 | 4020062732140 |
[1,4,17,80,403,2128,11628,65208,373175,2170740, 12797265,76292736,459162452,2786017120, 17024247304,104673837384,647113502847, 4020062732140] |