The following is a skew Hadamard matrix of order 4·57 = 228 constructed from a new set of good matrices of order 57 found by MathCheck. Prior to our work, searches had only been run . The coloured squares represent one and the white squares represent negative one and each good matrix is highlighted using a different colour. The colour scheme based on the one used in  of a Hadamard matrix of order 4·23 = 92 using Williamson matrices of order 23.
