# What a Coincidence!

Level pending

Let $$s(n)$$ denote the number of positive integers $$k$$ less than or equal to $$n$$ such that for all positive integers $$d$$ satisfying $$1 < d < k$$, we have $$d^2 \not| k$$. Let $$t(n)$$ denote the number of positive integers $$k$$ less than or equal to $$n$$ such that $$\gcd(k, n) = 1$$. Find the least positive integer $$a$$ such that $20s(a) - t(20.13a) = 0$

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