Andrica's conjecture (named after Dorin Andrica) is a conjecture regarding the gaps between prime numbers.
The conjecture states that the inequality
holds for all , where is the nth prime number. If denotes the nth prime gap, then Andrica's conjecture can also be rewritten as
Imran Ghory has used data on the largest prime gaps to confirm the conjecture for up to 1.3002 × 1016. Using a table of maximal gaps and the above gap inequality, the confirmation value can be extended exhaustively to 4 × 1018.