An infinite family of Hadamard matrices constructed from Paley type matrices


Adda Farouk, Qing-Wen Wang




An n × n matrix whose entries are from the set {1, −1} is called a Hadamard matrix if HH = nI n. The Hadamard conjecture states that if n is a multiple of four then there always exists Hadamard matrices of this order. But their construction remain unknown for many orders. In this paper we construct Hadamard matrices of order 2q(q + 1) from known Hadamard matrices of order 2(q + 1), where q is a power of a prime number congruent to 1 modulo 4. We show then two ways to construct them. This work is a continuation of U. Scarpi`s in [7] and Dragomir- Ž Doković's in [10]