length n = 21
dimension k = 7
alphabet length q = 4

minimum distance d = 11

generator matrix:
000000100111111111111
000001011001111222333
000010023231123012013
000100011112323210310
001000011230023121131
010000023232311201301
100000023112300122133

projective group of automorphisms generated by:
0000010
0000100
0010000
0000001
0100000
1000000
0001000

0000010
0000001
0001000
0100000
0000100
0010000
1000000