Modular multiplicative inverse (source code)

= Modular multiplicative inverse
{title2=$a^{-1}\pmod n$}
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A modular multiplicative inverse of $a$ modulo $n$ is a residue $a^{-1}$ satisfying $aa^{-1}\equiv1\pmod n$. It exists exactly when $\gcd(a,n)=1$.

= Modular inverse
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