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 A156560 #28 Sep 04 2024 18:57:21
%S A156560 3,11,59,251,1019,4091,262139,1048571,67108859,4294967291,68719476731,
%T A156560 72057594037927931,73786976294838206459,
%U A156560 332306998946228968225951765070086139,1361129467683753853853498429727072845819,1427247692705959881058285969449495136382746619
%N A156560 Primes of the form 2^n-5.
%C A156560 If p = 2^n-5 is prime, then p*2^(n-1) is abundant with abundance 4 (see A088832). - _Davide Rotondo_, Oct 25 2020
%H A156560 Vincenzo Librandi, <a href="/A156560/b156560.txt">Table of n, a(n) for n = 1..28</a>
%F A156560 a(n) = 2^A059608(n) - 5.
%t A156560 Select[Table[2^n-5,{n,2,400}],PrimeQ] (* _Vincenzo Librandi_, Jul 26 2012 *)
%o A156560 (Magma) [ a: n in [2..500] | IsPrime(a) where a is 2^n-5 ];
%o A156560 (PARI) for(n=1,300,q=2^n-5;if(isprime(q),print(q))) /* gives more terms in <10secs */ \\ _Joerg Arndt_, Dec 03 2010
%Y A156560 Corresponding n's are in A059608.
%Y A156560 Cf. A088832.
%K A156560 nonn
%O A156560 1,1
%A A156560 _Vincenzo Librandi_, Feb 10 2009
%E A156560 Edited by _Zak Seidov_