Maximal Binary Matrices and Sum of Two Squares
C. H. Yang · Mathematics of Computation · 1976
A maximal $( + 1, - 1)$-matrix of order 66 is constructed by a method of matching two finite sequences. This method also produced many new designs for maximal $( + 1, - 1)$-matrices of order 42 and new designs for a family of H-matrices of order ${26.2^n}$. A nonexistence proof for a $(\ast )$-type H-matrix of order 36, consequently for Golay complementary sequences of length 18, is also given.