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 A073428 #11 Jan 31 2025 17:32:02
%S A073428 3,13,911,5791,79111,105107,1232527,23252729,113151719,2527293133,
%T A073428 57911131517,991011031051,6769717375777,13579111315171,
%U A073428 135791113151719,4547495153555759,31517192123252729,719212325272931333,1131517192123252729,71921232527293133353
%N A073428 First n-digit prime in the concatenation of odd integers forbidding leading zeros.
%C A073428 Leading zeros are forbidden (cf. A073176).
%t A073428 ndpQ[n_] := First[n] != 0 && PrimeQ[FromDigits[n]]; With[{od=Flatten[ IntegerDigits/@ Range[1,501,2]]}, Table[ FromDigits/@ Select[Partition[ od,n,1], ndpQ,1],{n,20}]]//Flatten (* _Harvey P. Dale_, Feb 12 2013 *)
%K A073428 easy,nonn,base
%O A073428 1,1
%A A073428 _Zak Seidov_, Aug 22 2002
%E A073428 Corrected and extended by _Harvey P. Dale_, Feb 12 2013
%E A073428 Name modified by _Sean A. Irvine_, Jan 31 2025