One less than 10000.
The set of positive odd integers.
There are 80 such integers.
The squares -- nine of them.
405
There are 44 positive integers less than 2,010 that have an odd number of factors.
666 integers.
One less than 10000.
There are 130 positive integers less than 1,000 that are divisible by seven but not divisible by 11
There are 544 positive integers less than 1,000 that are either divisible by two or by 11.
The set of positive odd integers.
Eight.
6
There are 80 such integers.
7 of them.
The squares -- nine of them.
The sum of the first positive odd integers less than 101 is 10,000.