Problem 268
Counting numbers with at least four distinct prime factors less than 100
It can be verified that there are 23 positive integers less than 1000 that are divisible by at least four distinct primes less than 100.
Find how many positive integers less than 1016 are divisible by at least four distinct primes less than 100.
拥有四个小于100的不同质因数的数计数
可以验证，在小于1000的正整数中，有23个能够被至少四个小于100的不同质数整除。
在小于1016的正整数中，求出有多少个能够被至少四个小于100的不同质数整除。