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 A159293 #2 Mar 30 2012 17:26:29
%S A159293 3,5,13,73,241,241,2521,3361,15121,15121,55441,55441,4324321,4324321,
%T A159293 4324321,4324321,196035841,196035841,1862340481,1862340481,1862340481,
%U A159293 1862340481,10708457761,10708457761,214169155201,214169155201
%N A159293 a(n) = smallest prime congruent to 1 mod A051426(n).
%t A159293 L1=2;A1={3};Do[L1=LCM[L1,n];k=1;While[ !PrimeQ[p=k*L1+1],k++ ];Print[p];AppendTo[A1,n],{n,4,60,2}]
%Y A159293 A051426 Least common multiple of {2, 4, 6..., 2n}.
%K A159293 nonn
%O A159293 1,1
%A A159293 _Zak Seidov_, Apr 09 2009