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 A111349 #10 Mar 14 2015 10:02:02
%S A111349 1003,1004,1007,1009,1010,1012,1013,1015,1016,1018,1019,1021,1024,
%T A111349 1025,1030,1031,1040,1043,1049,1051,1054,1055,1060,1061,1063,1070,
%U A111349 1082,1085,1088,1091,1094,1096,1099,1100,1105,1106,1108,1112,1114,1118,1123,1126
%N A111349 Numbers n such that the result of swapping the 4th digit and the digit 3 positions from the last digit is prime.
%C A111349 Leading zeros are dropped.
%C A111349 Since these numbers are just digit permutations of the primes the sequence is obviously infinite. - _Charles R Greathouse IV_, Oct 20 2008
%o A111349 (PARI) swapn(n,d) = \ d is the digit position to swap { local(j,ln,x,s,y,y2,tmp); for(x=10^(d-1),10^(d-1)+n, s = Str(x); ln = length(s); y = eval(Vec(s)); tmp=y[d]; y[d]=y[ln-d+1]; y[ln-d+1]=tmp; y2=0; for(j=1,ln, y2+=y[j]*10^(ln-j); ); if(isprime(y2),print1(x",")) ) }
%Y A111349 Cf. A095179, A111347, A111348.
%K A111349 easy,nonn,base
%O A111349 1,1
%A A111349 _Cino Hilliard_, Nov 05 2005