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 Random Link ¯\_(ツ)_/¯ Feb 6, 2021 » 021. Amicable Numbers 8 min; updated Feb 6, 2021 Problem Statement Let $$d(n)$$ be defined as the sum of proper divisors of $$n$$ (numbers less than $$n$$ which divide evenly into $$n$$). If $$d(a) = b$$ and $$d(b) = a$$, where $$a \neq b$$, then $$a$$ and $$b$$ are an amicable pair and each of $$a$$ and $$b$$ are called amicable numbers. For example, the proper divisors of $$220$$ are $$1, 2, 4, 5, 10, 11, 20, 22, 44, 55, 110$$; therefore $$d(220) = 284$$....