length n = 21
dimension k = 5
alphabet length q = 4

minimum distance d = 13

generator matrix:
000000111100111111111
001111000011001111231
000023002313130022131
110000230013231201031
232300000023132110101

projective group of automorphisms generated by:
00010
00100
10000
00001
01000

00100
00010
10000
01000
00001