4
$\begingroup$

I'm trying to solve this little problem. So far no luck. Could anyone help? Thanks in advance :)

What is the ten digit number such that the i-th digit is the number of i's in the number ( 0<= i <= 9) (the 0th position is number of zeros in the number, the 1st position is number of ones in the number,…)?

  • 2
    http://en.wikipedia.org/wiki/Self-descriptive_number2011-05-17

1 Answers 1

3

Here is one solution: $6210001000$ $(0123456789)$

  • 0
    A more general version of this question came up recently. Put 6210001000 in the search box to see it.2014-06-28