# Concept derivation guides

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Concept guide



## [Divisor-poset inversion of an affine function](/en/derivations/derivation-mko-mobius-inversion-finite-divisors-01/?from=%2Fen%2Fderivations%2F%3Fq%3Dmko-mobius-inversion-finite-divisors)

For f(k)=2k+1 at n=6, F(6)=28 and inversion returns f(6)=13; n=1 roundtrips too.

Mobius inversion on finite divisor sets

derivation-mko-mobius-inversion-finite-divisors-01





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