# Maths

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Can someone use mod to prove that 10^(3n + 1) cannot be represented as the sum of two cubes.

And make it very detailed please.

• Maths -

I know your are suffering Sean, so i'll tell u. USE base 7. Cubes mod 7 cant have a residue of 3 or 4. 10 ^ 3n + 1 dose and only has a residue of 10 ^ 3n +1. So there u go sean yu.

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