True or False (or Ambiguous)?
The sum of all the reciprocals of the divisors of a perfect number is ALWAYS 2
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It's true since,
n n + ⋯ + c + b + a = 2 n ⟹ a n + b n + ⋯ = 2 n ⟹ a 1 + b 1 + ⋯ = 2
I don't follow your argument... Are a , b , c , … the divisors of n ? If so, why are you dividing by n in the first equation? And I don't see how the second equation follows from the first.
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Call the perfect number x
Factors of x are F 1 , F 2 , F 3 … F n
∑ i = 1 n F n = 2 x
F 1 1 + F 2 1 … + F n 1 = x F 1 x + F 2 x … + F n x
Notice that because x is a perfect number, F 1 x + F 2 x … + F n x is equal to ∑ i = 1 n F n = 2 x
x 2 x = 2