Primes of the form n^2 + 1

GPTKB entity

Statements (26)
Predicate Object
gptkbp:instanceOf class of prime numbers
gptkbp:defines prime numbers that can be written as n^2 + 1 for some integer n
gptkbp:example 2
101
17
197
257
37
401
5
577
677
https://www.w3.org/2000/01/rdf-schema#label Primes of the form n^2 + 1
gptkbp:openProblem It is unknown whether there are infinitely many primes of the form n^2 + 1
gptkbp:property no known simple formula for generating only primes of this form
for n > 1, n^2 + 1 is always odd
n must be even for n^2 + 1 to be even, but only n=1 gives 2 as a prime
if n is even and greater than 2, n^2 + 1 is odd and greater than 2
if n is divisible by 3, n^2 + 1 is congruent to 1 mod 3
gptkbp:relatedTo Landau's fourth problem
quadratic primes
gptkbp:sequence OEIS:A002496
gptkbp:studiedBy gptkb:Edmund_Landau
gptkbp:studiedIn number theory
gptkbp:bfsParent gptkb:A002487
gptkbp:bfsLayer 7