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Number of composite numbers bounded inclusively between p(n+1) and 2*p(n) where p(x) is prime(x).
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%I #6 Oct 01 2019 15:58:41

%S 1,1,3,2,7,7,12,12,13,22,19,25,31,31,33,37,45,44,51,56,55,61,63,66,75,

%T 80,81,87,88,82,101,103,111,105,121,120,124,132,134,140,148,142,158,

%U 158,164,156,165,182,188,188,189,199,193,205,210

%N Number of composite numbers bounded inclusively between p(n+1) and 2*p(n) where p(x) is prime(x).

%F a(n) = A062234(n) - A070046(n) + 1 = A120632(n) - A040976(n+1).

%t Table[Count[Range[Prime[n+1],2Prime[n]],_?CompositeQ],{n,60}] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Oct 01 2019 *)

%K nonn

%O 1,3

%A _Lekraj Beedassy_, Jun 21 2006

%E Definition clarified by _Harvey P. Dale_, Oct 01 2019