A set of positive integers is called sum-free if the
equation
has no solutions , , . The probability that a random sum-free set consists entirely of oddintegers is known to satisfy
The value of the constant is Cameron's sum-free set constant.
Cameron, P. J. "Cyclic Automorphisms of a Countable Graph and Random Sum-Free Sets." Graphs and Combinatorics1, 129-135,
1985.Cameron, P. J. "Portrait of a Typical Sum-Free Set."
In Surveys
in Combinatorics 1987 (Ed. C. Whitehead). New York: Cambridge University
Press, 13-42, 1987.Finch, S. R. "Cameron's Sum-Free Set Constant."
§2.25 in Mathematical
Constants. Cambridge, England: Cambridge University Press, pp. 180-183,
2003.
is called sum-free if the
equation 
has no solutions 
, 
, 
. The probability that a random sum-free set 
consists entirely of odd integers is known to satisfy
is Cameron's sum-free set constant.
