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The only odd untouchable (Posted on 2016-04-12)

An untouchable number is a positive integer that is not the sum of the proper divisors of any number(see OEIS A005114).

It is thought that 5 is the only odd untouchable number.

Why?

No Solution Yet Submitted by Ady TZIDON

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	Subject	Author	Date
	Goldbach Solution	Brian Smith	2016-04-12 12:37:55

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