Seven Digit Self-Describing Number

Logic Level 2

Find the seven-digit number with the property that the $n$ th digit is the number of times the digit $(n - 1)$ appears in the number.

For example, the five-digit number with this property is 21200, because there are 2 zeros, 1 one, 2 twos, 0 threes, and 0 fours.

3 solutions

Ferren Alwie
Jan 14, 2016

Theresia V
Jan 14, 2016

In solving this question, we have to remember that all the digits of the number have to add up to 7.

Atul Shivam
Jan 14, 2016

I've tried various combinations an finally got $3211000$ which has $3$ zeroes, $2$ ones , $1$ two and $1$ three, $0$ four , $0$ five and $0$ six

so the correct answer is $\boxed{3211000}$