overview of finiteness proof Gerog comment "not helpful", adding more intuitions of "closed forms"
1 15
2 34
3 72
4 148
5 300
6 604
7 1212
8 2428
9 4860
10 9724
11 19452
12 38908
13 77820
14 155644
15 311292
16 622588
17 1245180
18 2490364
19 4980732