标题: 2010年Puzzleup数学竞赛−第19题:Odd Numerals [打印本页] 作者: zyzme 时间: 2010-12-19 18:11 标题: 2010年Puzzleup数学竞赛−第19题:Odd Numerals Odd Numerals
When all integers from 1 to X are written on a piece of paper, the number of odd numerals used are two times X.
What is the maximum possible value for X?
Example: If all integers from 1 to 15 are written, the number of odd numerals used is 14.