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A095314
Primes in whose binary expansion the number of 1 bits is > 2 + number of 0 bits.
6
7, 23, 29, 31, 47, 59, 61, 79, 103, 107, 109, 127, 191, 223, 239, 251, 311, 317, 347, 349, 359, 367, 373, 379, 383, 431, 439, 443, 461, 463, 467, 479, 487, 491, 499, 503, 509, 607, 631, 701, 719, 727, 733, 743, 751, 757, 761, 823, 827, 829, 859
OFFSET
1,1
MAPLE
f:= proc(n) local L, d, s;
if not isprime(n) then return false fi;
L:= convert(n, base, 2);
convert(L, `+`) > nops(L)/2+1
end proc:
select(f, [seq(i, i=3..1000, 2)]); # Robert Israel, Oct 26 2023
MATHEMATICA
n1Q[p_]:=Module[{be=IntegerDigits[p, 2]}, Total[be]>2+Count[be, 0]]; Select[ Prime[ Range[150]], n1Q] (* Harvey P. Dale, Oct 26 2022 *)
PROG
(PARI) B(x) = { nB = floor(log(x)/log(2)); b1 = 0; b0 = 0;
for(i = 0, nB, if(bittest(x, i), b1++; , b0++; ); );
if(b1 > (2+b0), return(1); , return(0); ); };
forprime(x = 2, 859, if(B(x), print1(x, ", "); ); );
\\ Washington Bomfim, Jan 12 2011
CROSSREFS
Complement of A095315 in A000040. Subset of A095286. Subset: A095318. Cf. also A095334.
Sequence in context: A044068 A109992 A070330 * A038948 A019389 A056723
KEYWORD
nonn,base
AUTHOR
Antti Karttunen, Jun 04 2004
STATUS
approved