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A066148
Primes with an even number of 0's in binary expansion.
5
3, 7, 19, 31, 43, 53, 67, 73, 79, 97, 103, 107, 109, 127, 139, 149, 163, 197, 271, 283, 307, 313, 331, 367, 379, 397, 409, 419, 421, 431, 433, 439, 443, 457, 463, 487, 491, 499, 523, 547, 571, 593, 599, 619, 643, 673, 683, 691, 739, 751, 773, 797, 811, 821
OFFSET
1,1
MATHEMATICA
Select[Prime[Range[200]], EvenQ[DigitCount[#, 2, 0]]&] (* Harvey P. Dale, Mar 04 2017 *)
PROG
(PARI): a066148(m) = local(p, v, z); forprime(p=2, m, v=binary(p); z=0; for(j=1, matsize(v)[2], if(v[j]==0, z++)); if(z%2==0, print1(p, ", "))) a066148(850)
(PARI) f(p)={v=binary(p); s=0; for(k=1, #v, if(v[k]==0, s++)); return(1-s%2)}; forprime(p=3, 821, if(f(p), print1(p, ", "))) \\ Washington Bomfim, Jan 14 2011
(PARI) forprime(p=2, 10^3, if( #select(x->x==0, digits(p, 2))%2==0, print1(p, ", "))); \\ Joerg Arndt, Jun 16 2018
CROSSREFS
KEYWORD
nonn,easy,base
AUTHOR
R. K. Guy, Dec 13 2001
EXTENSIONS
More terms from Vladeta Jovovic and Klaus Brockhaus, Dec 13 2001
STATUS
approved