1022 Graph labelling
40.6 A perfect magic circle
1261
27
68
18
70
16
63
257412672165237214137520662264157326(^1960)
69
17
71
24
62
29
36 59
50
38
48
31
57
42
44
35
53
33
55
40
46
45
43
52
34
54
32
47
41
58
28
51
37
49
(^3956)
30