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PROJECT EULER · #0217

Balanced Numbers

Statement only · SolvedOriginal problem ↗

A positive integer with k (decimal) digits is called balanced if its first k/2 digits sum to the same value as its last k/2 digits, where x, pronounced ceiling of x, is the smallest integer x, thus π=4 and 5=5.

So, for example, all palindromes are balanced, as is 13722.

Let T(n) be the sum of all balanced numbers less than 10n.
Thus: T(1)=45, T(2)=540 and T(5)=334795890.

Find T(47)mod315.

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