A continuous bus tickets' tape consists of one million tickets numbered from 000000 to 999999.
All tickets are white, except those in which the sum of digits in the even positions equals the sum of digits in the odd positions: those are blue.
What is the largest distance (in numbers) between 2 consecutive blue tickets?
The greatest difference between the sums is 27 given by 909090
Going backwards from there the number with 0 difference is 908919
Going forwards the number with 0 difference is 909909
for a difference of 990.
Interchanging each number with 1000000itself should also give an equal gap.

Posted by Jer
on 20150326 14:18:55 