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Diagonal arguments

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Quick description

Prerequisites

Example 1

Given a bijection from the naturals to the reals, write the element mapped to by n as Rn and the dth digit after the decimal place as Rn(d) Then let C(d) = 6 if Rd(d) != 6 , 7 otherwise. Then C(d) is no equal to any Rn therefore we have a contradiction.

General discussion