And, the GCD function helps to generate the greatest common divisor of two or more integers. In simple, it’s the highest common factor or integer that can divide integers present in a set.

Richard Steiner, Modular Divisor Functions and Quadratic Reciprocity, The American Mathematical Monthly, Vol. 117, No. 5 (May 2010), pp. 448-451 ...

D. BERKANE, O. BORDELLÈS, O. RAMARÉ, EXPLICIT UPPER BOUNDS FOR THE REMAINDER TERM IN THE DIVISOR PROBLEM, Mathematics of Computation, Vol. 81, No. 278 (APRIL 2012 ...