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A127441
Numbers n such that between n and n+sqrt(n) there are no primes.
2
3, 7, 8, 13, 23, 24, 31, 113, 114, 115, 116
OFFSET
1,1
COMMENTS
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
MATHEMATICA
a = {}; Do[If[PrimePi[x + x^(1/2)] - PrimePi[x] == 0, AppendTo[a, x]], {x, 1, 249900000000000}]; a
PROG
(PARI) isok(n) = primepi(n+sqrtint(n)) == primepi(n); \\ Michel Marcus, Nov 07 2013
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Artur Jasinski, Jan 14 2007
STATUS
approved