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 A134854 #4 Mar 30 2012 17:22:47 %S A134854 7,13,41,113,97,193,641,769,11777,13313,59393,12289,40961,114689, %T A134854 163841,2424833,6946817,786433,5767169,7340033,23068673,155189249, %U A134854 595591169,1224736769,167772161,469762049,2281701377,3489660929,12348030977 %N A134854 Least prime of the form 1 + p*2^n, where p is an odd prime. %C A134854 a(n) least prime such that A098006(pi(a(n))) = 2^(n-1). See A134855 for the values of p. %H A134854 T. D. Noe, <a href="/A134854/b134854.txt">Table of n, a(n) for n=1..1000</a> %t A134854 Table[Select[1+2^n*Prime[Range[2,100]], PrimeQ, 1][[1]], {n,41}] %K A134854 nonn %O A134854 1,1 %A A134854 _T. D. Noe_, Nov 13 2007