How Euler Secured The World

Leonhard Euler is defined as the father of mathematics. He lived from 1707 to 1783, and had a stunning research career, including contributions to mechanics, music and fluid dynamics. His shadow thus looms large over our modern world, including within cryptography.

One of his great theorems defined that:

aᴺ⁻¹≡1 (mod N)

The key factor here is that a and N should not share the same factors. We often define this as gcd(a,N)=1, and where gcd() is the greatest common denominator. If we use a few values of a and N we see [Try]:

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Prof Bill Buchanan OBE

Prof Bill Buchanan OBE

Professor of Cryptography. Serial innovator. Believer in fairness, justice & freedom. Based in Edinburgh. Old World Breaker. New World Creator. Building trust.