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Semi-automorphisms of Hadamard matrices

Published online by Cambridge University Press:  24 October 2008

Marshall Hall Jr
Marshall Hall Jr
Affiliation:
California Institute of Technology
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Extract

A Hadamard matrix Hn is an n by n matrix H = [hij], i, j = 1, …, n in which every entry hij is + 1 or − 1, such that

It is well known that possible orders are n = 1, 2 and n = 4m. An automorphism α of H is given by a pair P, Q of monomial ± 1 matrices such that

Here P permutes and changes signs of rows, while Q acts similarly on columns.

Type
Research Article
Information
Mathematical Proceedings of the Cambridge Philosophical Society , Volume 77 , Issue 3 , May 1975 , pp. 459 - 473
Copyright
Copyright © Cambridge Philosophical Society 1975

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References

REFERENCES

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