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 A105139 #15 Jul 02 2025 15:21:52 %S A105139 0,1,6,15,18,27,28,43,45,52,60,61,70,73,78,81,85,90,96,97,111,112,117, %T A105139 138,147,151,153,165,172,178,187,192,196,202,208,210,211,213,216,222, %U A105139 228,231,235,243,250,252,253,255,262,265,270,280,291,298,301,312,325,328,330,337 %N A105139 Numbers k such that 512*k+257 is prime. %H A105139 Vincenzo Librandi, <a href="/A105139/b105139.txt">Table of n, a(n) for n = 1..1000</a> %t A105139 Select[Range[0, 500], PrimeQ[512 # + 257]&] (* _Vincenzo Librandi_, Jan 08 2013 *) %o A105139 (Magma) [n: n in [0..350] | IsPrime(512*n + 257)]; // _Vincenzo Librandi_, Jan 08 2013 %o A105139 (PARI) is(n)=isprime(512*n+257) \\ _Charles R Greathouse IV_, Jun 06 2017 %Y A105139 Cf. A095278, A105133-A105140, A002145, A007521, A105126-A105132. %K A105139 nonn,easy %O A105139 1,3 %A A105139 _N. J. A. Sloane_, based on correspondence from _Marco Matosic_, Apr 11 2005