Erdős offered a prize for a proof of the proposition that "If the
sum of reciprocals of a set of integers diverges, then that set contains arbitrarily
long arithmetic progressions." This conjecture remains open. Erdős also
offered
for an asymptotic formula for
, the largest possible cardinality of a subset of
that does not contain a 3-term
arithmetic progression. The conjecture is problem 3
in the Erdős problems collection (Bloom 2026).
Erdős-Turán Conjecture
See also
A-Sequence, B2-Sequence, Erdős Problems, Szemerédi's TheoremPortions of this entry contributed by Kevin O'Bryant
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References
Bloom, T. F. "Erdős Problem 3." Erdős Problems. Oct. 1, 2026. https://www.erdosproblems.com/3.Erdős, P. and Turán, P. "On Some Sequences of Integers." J. London Math. Soc. 11, 261-264, 1936.Green, B. and Tao, T. "The Primes Contain Arbitrarily Long Arithmetic Progressions." Ann. Math. 167, 481-547, 2008. https://doi.org/10.4007/annals.2008.167.481.Referenced on Wolfram|Alpha
Erdős-Turán ConjectureCite this as:
Weisstein, Eric W., with contributions by Kevin O'Bryant. "Erdős-Turán Conjecture." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/Erdos-TuranConjecture.html