# 2015 Countdown Problem #6: Summing Up The Years - Revisited

Last year I've posted the following problem (Summing up the Years) which has been reshared on Brilliant's official Facebook page, and this year I've decided to introduce a twist to this deceptively simple problem:

Find the last digit of $\sum_{i=0}^{2015} ( ((2015^{i})^{i}) (i^{2015}) )$

This problem is part of the set 2015 Countdown Problems.

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