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 A178382 #3 Jan 03 2013 12:39:31 %S A178382 2,3,5,7,17,29,41,43,61,79,101,131,137,149,173,197,211,223,227,229, %T A178382 233,239,241,251,271,281,293,307,311,331,353,397,439,449,463,523,569, %U A178382 593,607,641,683,691,727,733,751,761,787,821,853,859,919,947,953,983,1031 %N A178382 Primes that are in classes k+ and k- for some k in the Erdős-Selfridge classification of primes. %C A178382 The first five terms are the only primes in both class 1+ and class 1-. The Mathematica program assigns 2 and 3 to class 0 in order to simplify the algorithm; they are actually in classes 1- and 1+. %F A178382 Prime(n) such that A126433(n) = A126805(n). %t A178382 classp[2]=0; classp[3]=0; SetAttributes[classp, Listable]; classp[p_] := classp[p] = 1+Max@@classp[First/@FactorInteger[p+1]]; classm[2]=0; classm[3]=0; SetAttributes[classm, Listable]; classm[p_] := classm[p] = 1+Max@@classm[First/@FactorInteger[p-1]]; Select[Prime[Range[1000]], classp[ # ]==classm[ # ]&] %K A178382 nonn %O A178382 1,1 %A A178382 _T. D. Noe_, May 26 2010