{ "id": "2107.05525", "version": "v1", "published": "2021-07-12T15:54:05.000Z", "updated": "2021-07-12T15:54:05.000Z", "title": "Intersections of binary quadratic forms in primes] Intersections of binary quadratic forms in primes and the paucity phenomenon", "authors": [ "Alisa Sedunova" ], "comment": "Accepted for a publication in J. Number Theory", "categories": [ "math.NT" ], "abstract": "The number of solutions to $a^2+b^2=c^2+d^2 \\le x$ in integers is a well-known result, while if one restricts all the variables to primes Erdos showed that only the diagonal solutions, namely, the ones with $\\{a,b\\}=\\{c,d\\}$ contribute to the main term, hence there is a paucity of the off-diagonal solutions. Daniel considered the case of $a,c$ being prime and proved that the main term has both the diagonal and the non-diagonal contributions. Here we investigate the remaining cases, namely when only $c$ is a prime and when both c,d are primes and, finally, when $b,c,d$ are primes by combining techniques of Daniel, Hooley and Plaksin.", "revisions": [ { "version": "v1", "updated": "2021-07-12T15:54:05.000Z" } ], "analyses": { "keywords": [ "binary quadratic forms", "intersections", "paucity phenomenon", "main term", "non-diagonal contributions" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }