**CloudStat**, and kindly contributed to R-bloggers)

A prime number (or a prime) is a natural number greater than 1 that has no positive divisors other than 1 and itself.

**R Language Code**

prime = function(n)

{

n = as.integer(n)

if(n > 1e8) stop(“n too large”)

primes = rep(TRUE, n)

primes[1] = FALSE

last.prime = 2L

fsqr = floor(sqrt(n))

while (last.prime <= fsqr)

{

primes[seq.int(2L*last.prime, n, last.prime)] = FALSE

sel = which(primes[(last.prime+1):(fsqr+1)])

if(any(sel)){

last.prime = last.prime + min(sel)

}else last.prime = fsqr+1

}

which(primes)

}

To list out the primes within 100, simply type the command:

prime(100)

Now, question is

*By listing the first six prime numbers: 2, 3, 5, 7, 11, and 13, we can see that the 6th prime is 13.*

*What is the 10 001st prime number?*

We simply accessing the elements of vector by using **[ and ]**

We first concatenate more than 10001 primes into prime2 variable by command prime(2000000). Then accessing the 10001st element of the vector and we get the 10001st prime number!

prime2 = prime(200000)

prime2[10001]

Enjoy ^^

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**CloudStat**.

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