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 A133979 #5 Apr 28 2015 15:02:11 %S A133979 747521,2333797,2337397,2337691,3373547,3373907,3378317,3379829, %T A133979 3574657,3639997,3733967,3746507,3777419,3784463,3789293,3791423, %U A133979 3795569,3798923,4389883,7548461 %N A133979 Home primes whose homeliness is greater than 12. %C A133979 Number of terms < 10^n: 0, 0, 0, 0, 0, 1, 20, .... %t A133979 lst = {}; f[n_] := FromDigits@ Flatten[ IntegerDigits@ Table[ #[[1]], {#[[2]]}] & /@ FactorInteger@n, 2]; h[n_] := NestWhileList[f@# &, n, !PrimeQ@# &, 1, 28]; Do[p = h[n][[ -1]]; If[ PrimeQ@p && p < 10^7 && p != n, Print[{n, p}]; AppendTo[lst, p]], {n, 2, 1000}]; %t A133979 d = 13 - 2; lsu = {}; Do[ If[ lst[[n]] == lst[[n + d]], AppendTo[ lsu, lst[[n]] ]], {n, 188004 - d - 1}]; Union@ lsu %Y A133979 Cf. A037274, A118756, A133957, A133959, A133961, A133963, A133965, A133967, A133969, A133971, A133973, A133975, A133977. %K A133979 nonn,base %O A133979 1,1 %A A133979 _Robert G. Wilson v_, Sep 30 2007