The modest state of knowledge

.

k\g

5

6

7

8

9

10

11

12

13

14

15

3

10

14

24

30

58

70

112

126

272

384

620

4

19

26

67

80

318

 

 

728

 

 

 

5

30

42

152

170

 

 

 

2730

 

 

 

6

40

62

294

312

 

 

 

7812

 

 

 

7

50

90

 

 

 

 

 

 

 

 

 

8

80

114

 

800

 

 

 

39216

 

 

 

9

98

146

 

1170

 

 

 

74898

 

 

 

10

126

182

 

1640

 

 

 

132860

 

 

 

11

160

240

 

 

 

 

 

 

 

 

 

12

203

266

 

2928

 

 

 

354312

 

 

 

13

240

 

 

 

 

 

 

 

 

 

 

14

312

366

 

4760

 

 

 

804468

 

 

 

15

504 

 

 

 

 

 

 

 

 

 

 

16

602 

 

 

 

 

 

 

 

 

 

 


This is the current state-of-the-art. Each number is a link to an actual graph of the stated order; this is the currently smallest known such graph. Values that are known to be sharp - in the most  cases because they either meet the Moore bound or are small enough that exhaustive searches  have been done, are in red.