There are many websites and online resources if one wants to know the number of prime numbers up to some $N$, there are online prime number calculators and many tables on various sites. Could anyone possibly point me to a website where I can do this for primes in residue classes?
I want to give an online resource for students in my class to be able to find the number of primes less than $N$ that are $a$ modulo $q$, kinda thing but I haven't been able to find one. I would greatly appreciate any information. Thank you very much!