An Online Service for Computing Hadamard Matrices
and Orthogonal Arrays of Strength 3

Introduction

Our service supplies the following:

1. an Hadamard matrix of order N for each N being a multiple of 4 and less than 664, except for the cases 452, 476, 508, 532 and 652;
2. a mixed orthogonal array of strength 3 with run size N at most 100.

Instructions

• You should press the GAP setup link to initialize the server.
• Then please choose the link Hadamard matrices to obtain an Hadamard matrix;
• or press the link Orthogonal arrays to get a minimal runsize strength 3 mixed orthogonal array.

Remark

The methods used in this website and the table of available strength 3 mixed orthogonal arrays are described in the Ph.D. thesis Computer-algebraic methods for the construction of designs of experiments by Nguyễn Văn Minh Mẫn, September 2005.

Credit

The interface of this website was made by Jan Willem Knopper, Mark Spanbroek and Rikko Verrijzer

Acknowledgment

This work was done under supervision of prof.dr. A.M. Cohen.

Addresses

The authors can be reached at
Department of Mathematics,
Eindhoven University of Technology,
The Netherlands

The bibliography of it can be found online.