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%I #4 May 05 2019 10:31:14
%S 3,5,7,19,53,59,97,103,149,157,163,197,227,241,331,347,379,409,443,
%T 449,457,503,509,547,607,659,691,709,751,821,911,953,971,977,997,1049,
%U 1109,1187,1193,1231,1237,1279,1409,1429,1439,1487,1499,1531,1583,1663,1721
%N Primes p such that the nearest integer to p*LN2 is prime, LN2=natural logarithm of 2, LN2~0.693147180..
%t lst={};Do[p=Prime[n];If[PrimeQ[Round[p*Log[2]]],AppendTo[lst,p]],{n,6!}];lst
%t nil2[n_]:=Module[{c=n Log[2],ce,fl},ce=Ceiling[c];fl=Floor[c];If[ c-fl < ce- c,PrimeQ[fl],PrimeQ[ce]]]; Select[Prime[Range[300]],nil2] (* _Harvey P. Dale_, May 05 2019 *)
%Y Cf. A116671, A116968, A117763, A118484, A118625, A118786, A118796
%K nonn
%O 1,1
%A _Vladimir Joseph Stephan Orlovsky_, Dec 13 2009
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