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%I #17 Nov 22 2021 10:05:56
%S 3,7,8,13,23,24,31,113,114,115,116
%N Numbers n such that between n and n+sqrt(n) there are no primes.
%C If Oppermann's conjecture is true, then all terms are nonsquares. Data from A002386 and A005250 show that a(12) > 6787988999657777797 if it exists. Most likely there are no further terms. - _Chai Wah Wu_, Mar 08 2019
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Oppermann%27s_conjecture">Oppermann's conjecture</a>
%t a = {}; Do[If[PrimePi[x + x^(1/2)] - PrimePi[x] == 0, AppendTo[a, x]], {x, 1, 249900000000000}]; a
%o (PARI) isok(n) = primepi(n+sqrtint(n)) == primepi(n); \\ _Michel Marcus_, Nov 07 2013
%Y Cf. A000720, A002386, A005250, A028392.
%K nonn,more
%O 1,1
%A _Artur Jasinski_, Jan 14 2007
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