Hadamard matrices of orders 60 and 64 with automorphisms of orders 29 and 31

Makoto Araya, Masaaki Harada, Vladimir D. Tonchev

A classification of Hadamard matrices of order $2p+2$ with an automorphism of order $p$ is given for $p=29$ and $31$. The ternary self-dual codes spanned by the newly found Hadamar…