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import FormalConjecturesUtilPrimes and perfect squares
namespace PrimesAndPerfectSquares
Are there infinitely many primes $p$ such that $p - 1$ is a perfect square? In other words: Are there infinitely many primes of the form $n^2 + 1$?
@[category research open, AMS 11]
theorem infinite_prime_sq_add_one :
answer(sorry) ↔ {n : ℕ | Prime (n^2 + 1)}.Infinite := ⊢ True ↔ {n | Prime (n ^ 2 + 1)}.Infinite
All goals completed! 🐙
end PrimesAndPerfectSquares