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 A048553 #17 Sep 30 2015 08:53:44 %S A048553 11,113,11311,113111,1131113,11311133,1131113353,113111335313, %T A048553 11311133531339,113111335313399,1131113353133993,113111335313399321, %U A048553 11311133531339932153,1131113353133993215379,113111335313399321537911 %N A048553 a(n+1) is next smallest prime beginning with a(n), initial prime is 11. %H A048553 Clark Kimberling, <a href="/A048553/b048553.txt">Table of n, a(n) for n = 0..498</a> %p A048553 f:= proc(n) %p A048553 local p, d; %p A048553 for d from 1 do %p A048553 p:= nextprime(n*10^d); %p A048553 if p < (n+1)*10^d then return p fi %p A048553 od %p A048553 end proc: %p A048553 A[1]:= 11: %p A048553 for n from 2 to 20 do A[n]:= f(A[n-1]) od: %p A048553 seq(A[n], n=1..20); # _Robert Israel_, Aug 16 2015 %t A048553 a = {11}; Do[k = 1; w = IntegerDigits[a[[n - 1]]]; %t A048553 While[CompositeQ@ FromDigits[Join[w, IntegerDigits@ k]], k += 2]; %t A048553 AppendTo[a, FromDigits[Join[w, IntegerDigits@ k]]], {n, 2, 15}]; a (* _Michael De Vlieger_, Sep 21 2015 *) %Y A048553 Cf. A048549-A048556, A261199-A261201, A261269-A261270. %K A048553 nonn,base %O A048553 0,1 %A A048553 _Patrick De Geest_, May 15 1999