Yes, it is. Probably the worst explanation of the Sieve of Eratosthenes I ever read, overall not bad. I recall the first programming problem I ever had in school was to find the prime numbers below 100 using Fortran. I didn't know about the Sieve of Eratosthenes, but did know that any composite number had to have at least one factor less than or equal to its square root.
If you pick a number, N, "at random" from the set of all integers, what is the approximate likelihood that it is prime? Curiously enough, 1/ln(N). (ln(*) is the natural logarithm of *). The expected number of primes in the interal M to N is equal to the integral from x = M to x = N of dx/ln(x). The approximation gets relatively better as M get large. (Limit as M -> Inf and M-N -> Inf of the integral over the count of primes approaches unity.)
Lol yes... No fault of the poster but as Cruz would say this article is to primes what Carter was to the Presidency.