This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
13 is in the sequence because 13 is prime and 13 = 1101_2. '1101' has three 1's and one 0. 3 > 1 + 1. - _Indranil Ghosh_, Feb 07 2017
B(x) = {nB = floor(log(x)/log(2)); b1 = 0; b0 = 0;
for(i = 0, nB, if(bittest(x,i), b1++;, b0++;); );
if(b1 > (b0+1), return(1);, return(0);); };
forprime(x = 3, 499, if(B(x), print1(x, ", "); ); );
\\ Washington Bomfim, Jan 11 2011
from sympy import isprime
i = 1
j = 1
while j <= 2000:
bi = bin(i)[2:]
if isprime(i) and bi.count("1") > 1 + bi.count("0"):
print(str(j) + " " + str(i))
j += 1
i += 1 # Indranil Ghosh, Feb 07 2017
13 is in the sequence because 13 = 1101_2. '1101' has three 1's and one 0. 3 = 2 + 1. - _Indranil Ghosh_, Feb 07 2017
Select[Prime[Range[100]],DigitCount[#,2,1]<3+DigitCount[#,2,0]&] (* Harvey P. Dale, Aug 12 2016 *)
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, 397, if(B(x), print1(x, ", "); ); );
\\ Washington Bomfim, Jan 12 2011
from sympy import isprime
i=j=1
while j<=250:
if isprime(i) and bin(i)[2:].count("1")<=2+bin(i)[2:].count("0"):
print(str(j)+" "+str(i))
j+=1
i+=1 # Indranil Ghosh, Feb 07 2017
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