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A195007 Number of primes in the range (n*sqrt(n-1), (n+1)*sqrt(n)]. 1

%I

%S 1,1,1,1,2,1,1,1,1,1,1,2,1,1,2,1,2,1,1,1,1,3,2,0,1,2,1,2,1,2,1,2,2,2,

%T 1,0,3,2,1,2,1,3,2,1,1,3,0,2,2,2,1,2,2,2,1,2,2,3,1,3,1,2,2,1,2,1,1,2,

%U 3,2,2,4,1,2,2,2,3,1,2,1,2,3,2,2,1,1

%N Number of primes in the range (n*sqrt(n-1), (n+1)*sqrt(n)].

%e a(1)=1`because 1*sqrt(1-1)<(prime 2)<=(1+1)*sqrt(1),

%e a(2)=1 because 2*sqrt(2-1)<(prime 3)<=(2+1)*sqrt(2).

%t Table[PrimePi[(n+1)*Sqrt[n]] - PrimePi[n*Sqrt[n-1]], {n, 100}] (* _T. D. Noe_, Sep 14 2011 *)

%Y Cf. A006005, A192454.

%K nonn

%O 1,5

%A _Juri-Stepan Gerasimov_, Sep 07 2011

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Last modified September 25 21:49 EDT 2022. Contains 356986 sequences. (Running on oeis4.)