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 A068659 #16 Dec 07 2016 16:44:11
%S A068659 101,131213,171617,313031,333233,434243,474647,494849,636263,777677,
%T A068659 898889,939293,117116117,119118119,127126127,133132133,151150151,
%U A068659 159158159,161160161,163162163,199198199,243242243,269268269,273272273,277276277
%N A068659 Primes formed from the concatenation of n, n-1 and n for some n > 0.
%H A068659 K. D. Bajpai, <a href="/A068659/b068659.txt">Table of n, a(n) for n = 1..10001</a>
%p A068659 for n from 1 to 1000 do a := n+10^( floor(log(n)/log(10)+0.000001 )+1)*(n-1); a := a+10^( floor(log(a)/log(10)+0.000001 )+1)*n; b[n] := a:end do:k := 0:for n from 2 to 1000 doif(isprime(b[n])) then k := k+1:c[k] := b[n]:end if:end do:seq(c[j],j=1..k);
%t A068659 A068659={}; Do[t=FromDigits[Flatten[IntegerDigits/@{(n+1),n,(n+1)}]]; If[PrimeQ[t], AppendTo[A,t]], {n,500}]; A068659 (* _K. D. Bajpai_, Jul 03 2014 *)
%K A068659 base,nonn
%O A068659 1,1
%A A068659 _Amarnath Murthy_, Mar 01 2002
%E A068659 More terms from _Sascha Kurz_, Mar 26 2002
%E A068659 101 inserted by _Ilya Gutkovskiy_, Dec 07 2016