Landau's problems are four conjectures about prime numbers posed by Edmund Landau in 1912, none of which are solved as of 2023:
Goldbach's conjecture: Every even integer (except 2) is the sum of two primes.
Twin prime conjecture: There are infinitely many primes p such that p+2 is also prime.
Legendre's conjecture: There is always a prime between any two perfect squares.
There are infinitely many primes of the form n^2+1.
How many of these conjectures will turn out to be true?
Related questions
@JosephNoonan May I ask how you know so much conjectures ? Are you a mathematician ?
@nlhm These are all famous problems in number theory, especially the Goldbach conjecture and twin prime conjecture. There's even a Wikipedia article for them: https://en.wikipedia.org/wiki/Landau%27s_problems
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