10digit, position in decimal representation equal to no of digits in number
Source: Lusophon 2015 CPLP P2
August 29, 2018
number theoryDigitDigitsdecimal representation
Problem Statement
Determine all ten-digit numbers whose decimal is given by such that for each integer with is equal to the number of digits equal to in this representation.
That is: the first digit is equal to the amount of "" in the writing of that number, the second digit is equal to the amount of "" in the writing of that number, the third digit is equal to the amount of "" in the writing of that number, ... , the tenth digit is equal to the number of "" in the writing of that number.