Here's another one very nice question...
Is it possible to arrange the integers 1,1,2,2,...,1998,1998 such that there are exactly i-1 other numbers between any two i's?
(Elaborate Explanation Required!)

• Puzzle can be solver if 0 is also given in sequence
  First write all odd like this
  ...9753113579...
  Than after completing this series write all even number with 0 in middle
  ...864202468...
  Now the whole sequence become
  (...9753113579...)(...864202468...)
• 10 years agoHelpfull: Yes(12) No(5)
• 1997 1995 ....9 7 5 3 11 3 5 7 9... 1995 1997 1998 1996 1994... 6 4 2 0 2 4 6.. 1994 1996 1998
• 9 years agoHelpfull: Yes(0) No(1)
• without zero , the odd and even number series can be put horizontally and vertically...
  ...8
  6
  4
  2
  ...9,7,5,3,1,1,3,5,7,9...
  2
  8
  6
  8...
  
  
• 8 years agoHelpfull: Yes(0) No(0)