Given an irrational number , let be the sequence for .
( is the floor-function.)
It can be proven that for any irrational there exist infinitely many values of such that the subsequence is palindromic.
The first values of that give a palindromic subsequence for are:
, , , , , , , , , , , , , , , , , , , .
Let be the sum of the first values of for which the corresponding subsequence is palindromic.
So .
Let be the set of positive integers, not exceeding , excluding perfect squares.
Calculate the sum of for . Give the last digits of your answer.
Write-up coming later
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