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A095075
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Primes in whose binary expansion the number of 1-bits is less than or equal to number of 0-bits.
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8
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2, 17, 37, 41, 67, 73, 97, 131, 137, 139, 149, 163, 193, 197, 257, 263, 269, 277, 281, 293, 337, 353, 389, 401, 449, 521, 523, 541, 547, 557, 563, 569, 577, 587, 593, 601, 613, 617, 641, 643, 647, 653, 659, 661, 673, 677, 709, 769, 773, 787
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OFFSET
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1,1
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LINKS
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EXAMPLE
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17 is in the sequence because 17_10 = 10001_2. '10001' has two 1's and three 0's.
37 is in the sequence because 37_10 = 100101_2. '100101' has three 1's and 3 0's. (End)
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MATHEMATICA
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Select[Prime[Range[150]], Differences[DigitCount[#, 2]][[1]] >= 0 &] (* Amiram Eldar, Jul 25 2023 *)
Select[Prime[Range[150]], DigitCount[#, 2, 1]<=DigitCount[#, 2, 0]&] (* Harvey P. Dale, Sep 27 2023 *)
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PROG
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(PARI) B(x) = {nB = floor(log(x)/log(2)); z1 = 0; z0 = 0;
for(i = 0, nB, if(bittest(x, i), z1++; , z0++; ); );
if(z1 <= z0, return(1); , return(0); ); };
forprime(x = 2, 787, if(B(x), print1(x, ", "); ); );
(Python)
from sympy import isprime
i=1
j=1
while j<=250:
if isprime(i) and bin(i)[2:].count("1")<=bin(i)[2:].count("0"):
print(str(j)+" "+str(i))
j+=1
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CROSSREFS
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KEYWORD
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nonn,easy,base
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AUTHOR
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STATUS
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approved
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