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 A114759 #10 Dec 05 2013 19:57:14
%S A114759 13,433,0,54323,654323,0,292827262524233,987654323,0,
%T A114759 1716151413121110983,181716151413121110983,0,1413121110987654323,
%U A114759 27262524232221201918171615143,0,1716151413121110987654323
%N A114759 Smallest prime of the form: n successive positive integers in descending order followed by a 3. a(3k) = 0 as no such prime exists.
%e A114759 a(4) = 54323, four successive positive integers 5,4,3,2 in descending order followed by a 3.
%t A114759 a[n_]:=If[Mod[n, 3]==0, 0, (For[m=1, (v={};Do[v=Join[v, IntegerDigits[k]], {k, m+n-1, m, -1}]);!PrimeQ[10FromDigits[v]+3], m++ ];10FromDigits[v] +3)];Table[a[n], {n, 17}] - Farideh Firoozbakht
%t A114759 f[n_] := Block[{t = Reverse@Range@n}, If[Mod[n, 3] == 0, 0, While[p = FromDigits@Flatten@IntegerDigits@Join[t, {3}]; ! PrimeQ@p, t++ ]; p]]; Array[f, 18] (* _Robert G. Wilson v_ *)
%Y A114759 Cf. A114754, A114755, A114756, A114757, A114758, A112716, A108145.
%K A114759 base,nonn
%O A114759 1,1
%A A114759 _Amarnath Murthy_, Jan 01 2006
%E A114759 Extended by _Robert G. Wilson v_, _Ray Chandler_ and _Farideh Firoozbakht_, Jan 02 2006