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A095287
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Primes in whose binary expansion the number of 1-bits is <= 1 + number of 0-bits.
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4
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2, 5, 17, 19, 37, 41, 67, 71, 73, 83, 89, 97, 101, 113, 131, 137, 139, 149, 163, 193, 197, 257, 263, 269, 271, 277, 281, 283, 293, 307, 313, 331, 337, 353, 389, 397, 401, 409, 419, 421, 433, 449, 457, 521, 523, 541, 547, 557, 563, 569, 577, 587
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graph;
refs;
listen;
history;
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internal format)
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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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5 is in the sequence because 5_10 = 101_2. '101' has two 1's and one 0.
17 is in the sequence because 17_10 = 10001_2. '10001' has two 1's and three 0's. (Stop)
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MATHEMATICA
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Select[Prime[Range[200]], DigitCount[#, 2, 1]<=1+DigitCount[#, 2, 0]&] (* Harvey P. Dale, Apr 18 2023 *)
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PROG
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(PARI)forprime(p=2, 587, v=binary(p); s=0; for(k=1, #v, s+=if(v[k]==1, +1, -1)); if(s<=1, print1(p, ", "))) \\ Washington Bomfim, Jan 13 2011
(Python)
from sympy import isprime
i=1
j=1
while j<=250:
if isprime(i) and bin(i)[2:].count("1")<=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,base,easy
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AUTHOR
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STATUS
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approved
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