##一进制:1-20如何表达
1
11
111
1111
11111
111111
1111111
...
##三进制:1-20如何表达,峰三进一
0 1 2 10
11 12 20
21 22 100
101 102 110
111 112 120
121 122 200
201 202 210
211 212 220
221 222 1000
1001 1002 1010
1011 1020 1021
1022 1100 1101
1102 1110
###7进制,0,1,2,3,4,5,6
0,1,2,3,4,5,6,
10,11,12,13,14,15,16,
20,21,22,23,24,25,26,
30,31,32,33,34,35,36,
40