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 A211486 #15 Jul 28 2025 00:01:57
%S A211486 11,17,29,53,101,197,389,773,49157,196613,1572869,12582917,50331653,
%T A211486 402653189,1610612741,12884901893,824633720837,54043195528445957,
%U A211486 432345564227567621,3458764513820540933,226673591177742970257413,59421121885698253195157962757
%N A211486 Primes of the form 5+3*2^k.
%H A211486 Vincenzo Librandi, <a href="/A211486/b211486.txt">Table of n, a(n) for n = 1..40</a>
%t A211486 Select[5+2^Range[0,2000]*3,PrimeQ]
%o A211486 (Magma) [ a: n in [0..250] | IsPrime(a) where a is 5+3*2^n ];
%o A211486 (PARI) {for(n=0, 80, if(isprime(k=5+3*2^n), print1(k, ", ")))}
%Y A211486 Cf. A057913 (n such that 3*2^n + 5 is prime).
%Y A211486 Cf. A057197, A144487.
%K A211486 nonn
%O A211486 1,1
%A A211486 _Vincenzo Librandi_, Apr 13 2012