A strong version of Andrica's conjecture can be formulated as follows: Except for p n ∈ {3, 7, 13, 23, 31, 113}, that is n ∈ {2, 4, 6, 9, 11, 30}, one has √ p n+1 − √ p n < 1 2 . While a proof is far out of reach I shall show that this strong version of Andrica's conjecture is unconditionally and explicitly verified for all primes below the location of the 81 st maximal prime gap, certainly for all primes p < 2 64 ≈ 1.844 × 10 19 . Furthermore this strong Andrica conjecture is slightly stronger than Oppermann's conjecture -which in turn is slightly stronger than both the strong and standard Legendre conjectures, and the strong and standard Brocard conjectures. Thus the Oppermann conjecture, and strong and standard Legendre conjectures, are all unconditionally and explicitly verified for all primes p < 2 64 ≈ 1.844 × 10 19 . Similarly, the strong and standard Brocard conjectures are unconditionally and explicitly verified for all primes p < 2 32 ≈ 4.294 × 10 9 .