“…The twelve columns are described by a shift sequence modulo 10. This shift sequence can be converted into a perfect shift sequence modulo 5, [4] : 3,2,2,4,0,3,-,3,0,4,2,2. This produces a perfect matrix, by using it to shift (cyclically) a ternary Legendre sequence of length 5: 0,1,-1,-1,1.…”