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 A180511 #19 Jan 12 2019 20:18:26
%S A180511 5,51,585,95325,1290555,252645135,3616814565,764877654105,
%T A180511 2484744621997515,37191016277640225,127631526564044465235,
%U A180511 29485995600356809139175,449832863112420158030205
%N A180511 Fermat quotients for base 4: (4^(p - 1) - 1)/p, where p = prime(n).
%p A180511 A180511:= n-> map (p-> (4^(p-1)-1)/p, ithprime(n)):
%p A180511 seq (A180511(n), n=2..20); # _Peter Luschny_, Jan 21 2010
%t A180511 Table[(4^(Prime[n] - 1) - 1)/Prime[n], {n, 2, 20}] (* _Alonso del Arte_, Jan 20 2011 *)
%Y A180511 Cf. A007663, A146211.
%K A180511 nonn
%O A180511 2,1
%A A180511 _Jani Melik_, Jan 20 2011