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 A105437 #10 Jul 31 2015 02:26:38
%S A105437 2,3,3,7,3,83,31,7,3,29,3,53,23,439,23,53,31,71,31,79,89,233,7,3,227,
%T A105437 487,281,31,7,227,47,439,29,47,349,491,43,31,23,7,919,701,229,283,281,
%U A105437 59,223,2693,53,67,239,2011,2113,467,41,601,587,311,337,2879,59,619,71
%N A105437 Smallest prime that remains prime when a string of n 1's is prepended to it.
%e A105437 a(3)=7 because it is the first prime before 31,59,61,71,73,97,... all remaining prime when 111 is prepended to each of them.
%t A105437 f[n_] := Block[{k = 1, t = Table[1, {n}]}, While[id = IntegerDigits[ Prime[k]]; id[[1]] == 1 || !PrimeQ[ FromDigits[ Join[t, id]]], k++ ]; Prime[k]]; Table[ f[n], {n, 0, 62}] (* _Robert G. Wilson v_, Apr 09 2005 *)
%Y A105437 Cf. A105436, A065584.
%K A105437 nonn,base
%O A105437 0,1
%A A105437 _Lekraj Beedassy_, Apr 08 2005
%E A105437 More terms from _Robert G. Wilson v_, Apr 09 2005