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 (wwigr.org), the twin prime conjecture (wwitp.org), and Legendre conjecture (wwileg.org). The same open pipeline and documented methodology drives all four sites.

Contact

Questions, corrections, or additions: admin@wwin2p1.org.

Sources of error

Acknowledgments

Data sources: arXiv, OpenAlex, zbMATH Open.

License and reuse

The data on this site is built from public sources (arXiv, OpenAlex, zbMATH) under their respective license terms. The compiled list and methodology are released under CC-BY 4.0: feel free to reuse with attribution.

Methodology and data

How the rankings are built, what is in the data, and what is deliberately left out is documented on the Methodology page. The full Top 100 is published as an open, downloadable dataset on the Data and citation page.

Contact and corrections

This is an independent, non-commercial directory built from public data, so some entries carry errors. To fix a profile, suggest someone missing, or ask not to be listed, see the Corrections and removal page, or email admin@wwin2p1.org. Every message is read and acted on by a person.