There is a program that generates those graphs for the small number of vertices.
http://users.cecs.anu.edu.au/~bdm/data/graphs.html
The following code converts the file with the g6 format to an array (it is written in python).
import numpy as np
file_contents = open("graph3c.txt", "r")
lines = file_contents.readlines()
for line in lines:
n = ord(line.split()[0][0]) - 63
h = ''
l = n - 1
for i in range(1,l):
temp = bin(ord(line.split()[0][i])-63)[2:]
if len(temp) < 6:
for k in range(6 - len(temp)):
h = h + '0'
h = h + temp
A = [[0]*n for j in range(n)]
k = 0;
for i in range(1,n):
for j in range(0,i):
A[i][j] = int(h[k])
A[j][i] = A[i][j]
k = k+1
```