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Primes in whose binary expansion the number of 1 bits is <= number of 0 bits minus 2.
4

%I #14 Dec 10 2017 13:16:34

%S 131,137,193,257,521,523,547,577,593,641,643,673,769,773,1031,1033,

%T 1049,1061,1091,1093,1097,1153,1217,1283,1289,1297,1409,1553,1601,

%U 2053,2063,2069,2081,2083,2087,2089,2099,2113,2129,2131,2137,2153

%N Primes in whose binary expansion the number of 1 bits is <= number of 0 bits minus 2.

%H Harvey P. Dale, <a href="/A095317/b095317.txt">Table of n, a(n) for n = 1..1000</a>

%H A. Karttunen and J. Moyer: <a href="/A095062/a095062.c.txt">C-program for computing the initial terms of this sequence</a>

%t Select[Prime[Range[400]],DigitCount[#,2,1]<=DigitCount[#,2,0]-2&] (* _Harvey P. Dale_, Dec 10 2017 *)

%o (PARI)forprime(p=2,2200,v=binary(p);s=0;for(k=1,#v,s+=if(v[k]==1,+1,-1));if(s<=-2,print1(p,", ")))

%o \\ _Washington Bomfim_, Jan 13 2011

%Y Complement of A095316 in A000040. Subset: A095321. Subset of A095071. Cf. also A095327.

%K nonn,base,easy

%O 1,1

%A _Antti Karttunen_, Jun 04 2004