Find prime numbers using Scala. Help me to improve

Question

I wrote this code to find the prime numbers less than the given number i in scala.

def findPrime(i : Int) : List[Int] = i match {
    case 2 => List(2)
           


        

Answer 1

  /**
   * @return Bitset p such that p(x) is true iff x is prime
   */
  def sieveOfEratosthenes(n: Int) = {
    val isPrime = mutable.BitSet(2 to n: _*)
    for (p <- 2 to Math.sqrt(n) if isPrime(p)) {
      isPrime --= p*p to n by p
    }
    isPrime.toImmutable
  }