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Mathematics

The Ramanujan Tau Function and Modular Forms

Quick fact

The Ramanujan tau function, defined by the coefficients of the modular discriminant, satisfies surprising congruences such as τ(n) ≡ σ₁₁(n) mod 691, which were first observed by Ramanujan.

Why this is interesting

You've probably heard of prime numbers, but what about a sequence of numbers that hides secrets about primes and appears from a simple infinite product?