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A095314 Primes in whose binary expansion the number of 1 bits is > 2 + number of 0 bits. 6

%I #18 Oct 26 2023 19:19:17

%S 7,23,29,31,47,59,61,79,103,107,109,127,191,223,239,251,311,317,347,

%T 349,359,367,373,379,383,431,439,443,461,463,467,479,487,491,499,503,

%U 509,607,631,701,719,727,733,743,751,757,761,823,827,829,859

%N Primes in whose binary expansion the number of 1 bits is > 2 + number of 0 bits.

%H Robert Israel, <a href="/A095314/b095314.txt">Table of n, a(n) for n = 1..10000</a>

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

%p f:= proc(n) local L,d,s;

%p if not isprime(n) then return false fi;

%p L:= convert(n,base,2);

%p convert(L,`+`) > nops(L)/2+1

%p end proc:

%p select(f, [seq(i,i=3..1000,2)]); # _Robert Israel_, Oct 26 2023

%t n1Q[p_]:=Module[{be=IntegerDigits[p,2]},Total[be]>2+Count[be,0]]; Select[ Prime[ Range[150]],n1Q] (* _Harvey P. Dale_, Oct 26 2022 *)

%o (PARI) B(x) = { nB = floor(log(x)/log(2)); b1 = 0; b0 = 0;

%o for(i = 0, nB, if(bittest(x,i), b1++;, b0++;); );

%o if(b1 > (2+b0), return(1);, return(0););};

%o forprime(x = 2, 859, if(B(x), print1(x, ", "); ); );

%o \\ _Washington Bomfim_, Jan 12 2011

%Y Complement of A095315 in A000040. Subset of A095286. Subset: A095318. Cf. also A095334.

%K nonn,base

%O 1,1

%A _Antti Karttunen_, Jun 04 2004

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Last modified April 25 14:55 EDT 2024. Contains 371989 sequences. (Running on oeis4.)