Step 1  
	Select any whole number. 
   Step 2  
	If it is an even number, divide by 2; if it is odd number multiply by 3 and add 1. 
   Step 3  
	Repeat the process mentioned in step 2 until you get the loop value 4, 2, 1 in 
	repetition. 

  Whole number is 15. 
  15 is an odd no; so (15 × 3) + 1 = 46 
  46 is an even no; so 46 / 2 = 23 
  23 is an odd no; so (23 × 3) + 1 = 70 
  70 is an even no; so 70 / 2 = 35 
  35 is an odd no; so (35 × 3) + 1 = 106 
  106 is an even no; so 106 / 2 = 53 
  53 is an odd no; so (53 × 3) + 1 = 160 
  160 is an even no; so 160 / 2 = 80 
  80 is an even no; so 80 / 2 = 40 
  40 is an even no; so 40 / 2 = 20 
  20 is an even no; so 20 / 2 = 10 
  10 is an even no; so 10 / 2 = 5 
  5 is an odd no; so (5 × 3) + 1 = 16 
  16 is an even no; so 16 / 2 = 8 
  8 is an even no; so 8 / 2 = 4 
  4 is an even no; so 4 / 2 = 2 
  2 is an even no; so 2 / 2 = 1 
  1 is an odd no; so (1 × 3) + 1 = 4 
  4 is an even no; so 4 / 2 = 2 
  2 is an even no; so 2 / 2 = 1 

  So the loop 4..2..1 goes on and on.