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.
%I A280872 #9 May 10 2019 17:10:27
%S A280872 8287,8311,8317,8423,8429,8527,8539,8563,8599,8627,8629,8647,8677,
%T A280872 8681,8689,8783,8807,8819,8821,8861,8933,8999,9011,9013,9043,9049,
%U A280872 9059,9109,9137,9157,9161,9277,9319,9323,9337,9371,9397,9419,9421,9433,9511,9547,9613,9619
%N A280872 Primes that have exactly 7 zeros and 7 ones in their binary expansion.
%H A280872 K. D. Bajpai, <a href="/A280872/b280872.txt">Table of n, a(n) for n = 1..189</a>
%e A280872 8287 is in the sequence because it is a prime and its binary expansion 10000001011111 contains exactly 7 zeros and 7 ones.
%e A280872 9161 is in the sequence because it is a prime and its binary expansion 10001111001001 contains exactly 7 zeros and 7 ones.
%p A280872 select(t -> isprime(t) and convert(convert(t,base,2),`+`)=7, [seq(i,i=2^13+1..2^14-1,2)]); # _Robert Israel_, Jan 09 2017
%t A280872 Select[Prime[Range[50000]], Count[IntegerDigits[#, 2], 0] == Count[IntegerDigits[#, 2], 1] == 7 &]
%t A280872 Select[FromDigits[#,2]&/@(Join[{1},#]&/@Permutations[ {1,1,1,1,1,1,0,0,0,0,0,0,0}]),PrimeQ]//Union (* _Harvey P. Dale_, May 10 2019 *)
%Y A280872 Cf. A000040, A007088, A014311, A066196.
%K A280872 nonn,base,fini,full
%O A280872 1,1
%A A280872 _K. D. Bajpai_, Jan 09 2017