Hostname: page-component-8448b6f56d-c47g7 Total loading time: 0 Render date: 2024-04-23T19:48:31.298Z Has data issue: false hasContentIssue false

Some Theorems on Difference Sets

Published online by Cambridge University Press:  20 November 2018

Henry B. Mann*
Affiliation:
Ohio State University
Rights & Permissions [Opens in a new window]

Extract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

A set a1 …, ak of different residues mod v is called a difference set (v, k, λ) (v>k > λ) if the congruence ai — ajd (mod v) has exactly λ solutions for d ≢ 0 (mod v). Singer [4] has demonstrated the existence of a difference set (v, k, 1) if k — 1 is a prime power, and difference sets for λ > 1 have been constructed by various authors; but necessary and sufficient conditions for the existence of a (v, k, λ) are not known. It has not been possible so far to find a difference set with λ = 1 if k — 1 is not a prime power and it has therefore been conjectured that no such difference set exists.

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 1952

References

1. Chowla, S. andRyser, H. J., Combinatorial problems, Can. J. Math., vol. 2 (1950), 9399.Google Scholar
2. Hall, Marshall Jr., Cyclic projective planes, Duke Math. J., vol. 14 (1947), 10791090.Google Scholar
3. Hall, Marshall Jr. and Ryser, H. J., Cyclic incidence matrices, Can. J. Math., vol. 4 (1951), 495502.Google Scholar
4. Singer, James, A theorem in finite projective geometry and some applications to number theory, Trans. Amer. Math. Soc, vol. 43 (1938), 377385.Google Scholar