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 A069611 #11 Dec 15 2017 17:35:52
%S A069611 9,7,1,9,17,13,33,23,7,77,31,59,51,27,7,269,439,11,429,163,39,11,463,
%T A069611 77,63,39,33,93,21,139,53,159,49,9,291,111,21,23,349,83,3,37,11,57,21,
%U A069611 219,507,1233,429,147,627,127,399,27,63,423,111,633,1391,297,831,283
%N A069611 a(1) = 9; a(n) = smallest number such that the juxtaposition a(1)a(2)...a(n) is a prime.
%e A069611 a(5) = 17 and the number 971917 is a prime.
%t A069611 a[1] = 9; a[n_] := a[n] = Block[{k = 1, c = IntegerDigits @ Table[ a[i], {i, n - 1}]}, While[ !PrimeQ[ FromDigits @ Flatten @ Append[c, IntegerDigits[k]]], k += 2]; k]; Table[ a[n], {n, 63}] (* _Robert G. Wilson v_, Aug 05 2005 *)
%Y A069611 Cf. A069602, A069604, A046259, A074345, A092528, A069603, A069605, A069606, A069607, A069608, A069609, A069610, A069611, A111525.
%K A069611 nonn,base
%O A069611 1,1
%A A069611 _Amarnath Murthy_, Mar 26 2002
%E A069611 More terms from _Jason Earls_, Jun 13 2002