title: Prime number lazy sequence
body: <p>I am new in F# and I am just wondering if is there any way to get lazy sequence of prime numbers in F#.</p>
  
  <p>In Haskell I use next code:</p>
  
  <pre><code>primes :: [Integer]
  primes = sieve[2..]
         where sieve (p:xs) = p : sieve [x | x &lt;- xs, x `mod` p &gt; 0]
  </code></pre>
  
  <p>In F# I can check if is the number is prime:</p>
  
  <pre><code>let isPrime (number : bigint) =
      match number with
          | _ -&gt; seq { bigint(2) .. bigint(Math.Sqrt(float number))}
          |&gt; Seq.exists (fun x -&gt; if (number % x = bigint(0)) then true else false)
          |&gt; not
  </code></pre>
  
  <p>But I don't know how to convert it to lazy sequence.</p>