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Number of primes between prime(n) and prime(n)+2*log(prime(n)), exclusive.
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%I #6 Oct 23 2023 01:44:39

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

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

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

%N Number of primes between prime(n) and prime(n)+2*log(prime(n)), exclusive.

%C Inspired by A365573.

%F Conjecture: Limit_{N->oo} (Ratio_{n=1..N} a(n)=0) = 1/e^2 (A092553).

%t a[n_]:=PrimePi[Prime[n]+2Log[Prime[n]]]-PrimePi[Prime[n]]; Array[a,95] (* _Stefano Spezia_, Sep 30 2023 *)

%o (PARI) a(n) = primepi(prime(n)+2*log(prime(n))) - primepi(prime(n))

%Y Cf. A365573, A354841, A092553.

%K nonn

%O 1,12

%A _Alain Rocchelli_, Sep 30 2023