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A090430 a(n) = if Floor[2*Pi*PrimePi[m]/E] is prime then Floor[2*Pi*PrimePi[m]/E] 0

%I

%S 2,11,13,23,41,43,53,67,71,73,83,97,101,113,127,131,157,173,191,233,

%T 251,263,277,281,293,307,337,349,353,367,379,383,397,409,439,443,457,

%U 487,499,503,547,557,563,577,587,607,617,619,631,647,661,677,691,709,739

%N a(n) = if Floor[2*Pi*PrimePi[m]/E] is prime then Floor[2*Pi*PrimePi[m]/E]

%C An entropy power function based on the PrimePi distribution with N=n/PrimePi[n].

%C This function doesn't work as well as n/log(n).

%D C. E. Shannon, The Mathematical Theory of Communication, page 93

%t digits=25*200 f[n_]=Floor[2*Pi*PrimePi[n]/E] a=Delete[Union[Table[If [PrimeQ[f[n]]==True, f[n], 0], {n, 2, digits}]], 1]

%K nonn

%O 2,1

%A _Roger L. Bagula_, Jan 31 2004

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Last modified May 25 01:41 EDT 2019. Contains 323534 sequences. (Running on oeis4.)