Voronoi Diagrams of the Ulam Prime Spiral


The table below shows the primes that have 'less round' Voronoi cells than any smaller prime. I conjecture that this sequence is an infinite sequence - that is, there's no 'least round' voronoi cell. If you aren't sure what all this means, check out the explanation on the main page on this topic.













 
p"Centre"#VerticesVertex ListAreaPerimeter(P/2)2/A
2(1,0)5
(3

2
,1

2
), (3

2
,-3

2
), (1

6
,-5

6
), (-1

4
,0), (0,1

2
)
61

24
7

2
+4

3
�5
4.132018689726583
11(2,0)5
(3

2
,1

2
), (3

2
,-3

2
), (3,-2), (3,0), (2,1)
7

2
4+3

2
�2+1

2
�10
4.237705522975003
23(0,-2)4
(1

6
,-5

6
), (-3

2
,-5

2
), (-1,-4), (3

2
,-3

2
)
25

6
25

6
�2+2

3
�5+1

2
�10
4.821635921280641
31(3,3)4
(2,3), (3,2), (4,2), (4,5)
7

2
4+3�2
4.852937535496735
47(1,-3)4
(-1,-4), (3

2
,-3

2
), (3,-2), (1

2
,-9

2
)
5
5�2+�10
5.236067977499791
181(7,5)4
(7,4), (14

3
,19

3
), (6,7), (9,4)
16

3
2+16

3
�2+2

3
�5
5.706147946283363
229(8,-4)4
(6,-5), (9,-2), (9,-4), (8,-5)
4
4+4�2
5.82842712474619
1669(8,-20)3
(7,-21), (7,-18), (10,-21)
9

2
6+3�2
5.828427124746191
2153(-23,-13)5
(-24,-13), (-24,-15), (-62

3
,-35

3
), (-167

8
,-85

8
), (-22,-11)
143

24
2+16

3
�2+3

8
�10+5

24
�26
5.832955450142133
4603(-12,34)6
(-14,35), (-11,32), (-10,33), (-14,37), (-43

3
,37), (-29

2
,73

2
)
91

12
1

3
+8�2+2

3
�10
6.2375692795404465
5861(-30,-38)4
(-32,-39), (-28,-35), (-83

3
,-110

3
), (-30,-39)
19

3
2+19

3
�2+1

3
�26
6.32302992683966