雲泥有別 尘亦生辉

Prime DistanceTime Limit: 1000MS Memory Limit: 65536KTotal Submissions: 18909 Accepted: 5064DescriptionThe branch of mathematics called number theory is about p

In mathematics, the function d(n) denotes the number of divisors of positive integer n.For example, d(12)=6 because 1,2,3,4,6,12 are all 12's divisors.In this problem, given l,r and k, your task is to calculate the following thing :(∑i=lrd(ik))mod998