Binary (21,14)-code with minimal distance 4 

[100000000110000000010]
[010000000101000000010]
[001000000100100000010]
[000100000100010000010]
[000010000100001000010]
[000001000100000100010]
[000000100100000010010]
[000000010100000001010]
[000000001100000000110]
[000000000010001100010]
[000000000001001010010]
[000000000000101001010]
[000000000000011000110]
[000000000000000111111]