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About

Why this site exists

The n2+1 conjecture is one of four classical problems posed by Edmund Landau at the 1912 ICM. It asks whether infinitely many integers of the form n2+1 are prime. Nearly a century after Landau posed it and nearly five decades after Iwaniec result on almost-primes, the conjecture remains open. The community working on it sits at the intersection of sieve theory, the theory of polynomial prime values, and analytic number theory. This site is a starting point for anyone wanting to know who is working on this problem, where they are based, and what they have been writing.

Who built it

Steve Hubbard built this site as part of the Who's Who in Landau's Problems family, alongside sister sites for Goldbach conjecture (wwigb.org), the twin prime conjecture (wwitp.org), and Legendre conjecture (wwileg.org). The same open pipeline and documented methodology drives all four sites.