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 A127598 #6 May 05 2014 16:20:02
%S A127598 2,5,5,149,853,2389,17749,70997,218453,2708821,3495253,13981013,
%T A127598 39146837,492131669,626349397,27201459541,27201459541,297784399189,
%U A127598 297784399189,3665038759253,3665038759253,89426945725781
%N A127598 Least primes of the form k 4^n + (4^n-1)/3.
%t A127598 a = {}; Do[k = 0; While[ !PrimeQ[k 4^n + (4^n - 1)/3], k++ ]; AppendTo[a, k 4^n + (4^n - 1)/3], {n, 0, 50}]; a (*Artur Jasinski*)
%Y A127598 Cf. A035050, A007522, A127575, A127576, A127577, A127578, A127580, A127581, A087522, A127586, A127587, A127589, A127590, A127591, A127592, A127593, A127594, A127597.
%K A127598 nonn
%O A127598 1,1
%A A127598 _Artur Jasinski_, Jan 19 2007