N is a number with the property that all its digits are even.
3N also has that property.
Example: N=208 and 3N=624.

How many possible values of N have 22 digits? (3N may have 22 or 23 digits.)

For reference: Evened N and 3N is a version of this problem where N is only a 3 digit number.

.nm.nnn

Posted by golumqvoye on 2023-08-01 02:23:39