""" function computing the first n prime numbers using the algorithm of eratosthenes # Arguments - `n::Int`:number up to which prime numbers are searched """ function eratosthenes(n::Int) # gets one integer argument isaprime = trues(n) # generates n-element vector with true entries isaprime[1] = false # 1 is not a prime for i in 2:isqrt(n) # loop up to sqrt(n) if isaprime[i] for j in i^2:i:n # stepwidth is i isaprime[j] = false end end end return filter(x -> isaprime[x], 1:n) end