1 // Part 1 about the 3n+1 conjecture

     2 //==================================

     3 

     4 object CW6a {

     5 

     6 def collatz(n: Long): Long =

     7   if (n == 1) 1 else

     8     if (n % 2 == 0) 1 + collatz(n / 2) else 

     9       1 + collatz(3 * n + 1)

    10 

    11 

    12 def collatz_max(bnd: Long): (Long, Long) = {

    13   val all = for (i <- (1 to bnd.toInt).toList) yield collatz(i)

    14   val max = all.max

    15   (max, all.indexOf(max) + 1)

    16 }

    17 

    18 

    19 }

    20