The Erdős–Tenenbaum–Ford constant is a mathematical constant that appears in number theory. Named after mathematicians Paul Erdős, Gérald Tenenbaum, and Kevin Ford, it is defined as
where is the natural logarithm.
Following up on earlier work by Tenenbaum, Ford used this constant in analyzing the number of integers that are at most and that have a divisor in the range .
Multiplication table problem
For each positive integer , let be the number of distinct integers in an multiplication table. In 1960, Erdős studied the asymptotic behavior of and proved that
as .
Tenenbaum improved the Erdős multiplication table estimate, and Ford established an asymptotic best bound.
References
External links Decimal digits of the Erdős–Tenenbaum–Ford constant on the OEIS