octal     decimal       hex
 0            1           1          1   0
 1            2           2          2   1
 2            4           4          4   2
 3           10           8          8   3
 4           20          16         10   4
 5           40          32         20   5
 6          100          64         40   6
 7          200         128         80   7
 8          400         256        100   8
 9         1000         512        200   9
10         2000        1024        400  10
11         4000        2048        800  11
12        10000        4096       1000  12
13        20000        8192       2000  13
14        40000       16384       4000  14
15       100000       32768       8000  15
16       200000       65536      10000  16
17       400000      131072      20000  17
18      1000000      262144      40000  18
19      2000000      524288      80000  19
20      4000000     1048576     100000  20
21     10000000     2097152     200000  21
22     20000000     4194304     400000  22
23     40000000     8388608     800000  23
24    100000000    16777216    1000000  24
25    200000000    33554432    2000000  25
26    400000000    67108864    4000000  26
27   1000000000   134217728    8000000  27
28   2000000000   268435456   10000000  28
29   4000000000   536870912   20000000  29
30  10000000000  1073741824   40000000  30
31  20000000000  2147482648   80000000  31
32  40000000000  4294965296  100000000  32