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 A065539 #2 Mar 30 2012 17:30:37
%S A065539 13,131,1319,13217,132173,1321753,13217531,132175313,1321753177,
%T A065539 13217531771,132175317727,1321753177271,13217531772769,
%U A065539 132175317727727,1321753177277287,13217531772772933,132175317727729369
%N A065539 a(n) is smallest prime > 10*a(n-1), a(1) = 13.
%t A065539 NextPrim[n_Integer] := Block[ {k = n + 1}, While[ !PrimeQ[k], k++ ]; Return[k]]; a[1] = 13; a[n_] := NextPrim[ 10*a[n - 1]]; Table[ a[n], {n, 1, 20} ]
%Y A065539 Cf. A065122.
%K A065539 nonn
%O A065539 1,1
%A A065539 _Robert G. Wilson v_, Nov 28 2001