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 A152084 #11 Mar 15 2024 07:26:46 %S A152084 3,7,11,31,41,47,67,73,103,109,127,149,179,239,251,307,313,331,337, %T A152084 397,421,463,487,521,557,617,641,659,701,719,809,887,911,941,947,971, %U A152084 977,1019,1039,1063,1087,1117,1129,1213,1249,1327,1399,1423,1453,1567,1597 %N A152084 Primes p such that p + 2^floor(log_2(p)) is prime. %C A152084 a(n) + 2^floor(log_2(a(n))) = A152085(n). %C A152084 If a(n) is written in binary and the leftmost 1 is replaced with "10", then we would have the binary representation of A152085(n), which is a prime. %C A152084 Sequence A091932 contains the related primes p where p - 2^floor(log_2(p)) = prime. %H A152084 Robert Israel, <a href="/A152084/b152084.txt">Table of n, a(n) for n = 1..10000</a> %p A152084 filter:= n -> isprime(n) and isprime(n + 2^ilog2(n)): %p A152084 select(filter, [seq(i,i=3..10000,2)]); # _Robert Israel_, Mar 14 2024 %Y A152084 A152085, A091932 %K A152084 nonn %O A152084 1,1 %A A152084 _Leroy Quet_, Nov 23 2008 %E A152084 Extended by _Ray Chandler_, Nov 26 2008