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%I #8 Jul 22 2016 22:12:56
%S 0,0,0,1,1,1,0,1,2,2,1,2,2,2,2,3,2,2,1,1,2,3,2,2,2,2,3,3,2,3,2,3,3,3,
%T 4,4,3,3,3,4,3,3,2,2,3,3,3,3,3,3,3,4,3,3,4,4,5,5,4,4,3,4,4,4,4,5,4,4,
%U 4,4,4,4,3,3,3,3,3,3,3,3,3,4,3,4,4,4
%N Number of primes between n and n+log(n)^2.
%C According to Schinzel's formulation of Cramer's conjecture, a(n) > 0 for n > 7; see Guy.
%D R. K. Guy, Unsolved Problems in Number Theory, 3rd ed., Springer, 2004, page 11.
%H Clark Kimberling, <a href="/A275235/b275235.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) ~ log(n). - _Ilya Gutkovskiy_, Jul 22 2016
%t Table[PrimePi[n + Log[n]^2] - PrimePi[n], {n, 1, 200}]
%o (PARI) a(n) = primepi(n+log(n)^2) - primepi(n) \\ _Felix Fröhlich_, Jul 21 2016
%Y Cf. A000040.
%K nonn,easy
%O 1,9
%A _Clark Kimberling_, Jul 21 2016