On Sequences of Positive Integers
H. Davenport, Paul L. Erdos · Journal of the Indian Mathematical Society · 1951
Let a 1 , a 2 ,..., a m be any finite set of distinct natural numbers, and let b 1 , b 2 ,...be the sequence formed by all those numbers which are divisible by any of a 1 , a 2 ..., a m . This sequence has a density in the obvious sense and we denote this density by A(a 1 a 2 ,...a m ).