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 A083137 #23 Jan 17 2018 03:27:14 %S A083137 1,2,3,5,7,11,101,131,151,181,191,313,323,353,373,383,727,757,767,787, %T A083137 797,919,929,989,10001,10301,10501,10601,11111,11311,11411,12421, %U A083137 12721,12821,13031,13331,13831,13931,14141,14341,14741,14941,15151,15451 %N A083137 Smallest palindromic number relatively prime to all the previous terms. %C A083137 323 is the first composite entry. Conjecture: sequence is infinite. %H A083137 R. J. Mathar and Giovanni Resta, <a href="/A083137/b083137.txt">Table of n, a(n) for n = 1..10000</a> (first 966 terms from R. J. Mathar) %p A083137 isA002113 := proc(n) %p A083137 if digrev(n) = n then %p A083137 true; %p A083137 else %p A083137 false; %p A083137 end if; %p A083137 end proc: %p A083137 A083137 := proc(n) %p A083137 option remember; %p A083137 if n =1 then %p A083137 1; %p A083137 else %p A083137 for p from procname(n-1)+1 do %p A083137 if isA002113(p) then %p A083137 rpr := true; %p A083137 for i from 1 to n-1 do %p A083137 if igcd(procname(i),p) > 1 then %p A083137 rpr := false; %p A083137 break; %p A083137 end if; %p A083137 end do: %p A083137 if rpr then %p A083137 return p ; %p A083137 end if; %p A083137 end if; %p A083137 end do: %p A083137 end if; %p A083137 end proc: # _R. J. Mathar_, Aug 23 2014 %t A083137 a[1] = 1; a[n_] := a[n] = For[k = a[n-1]+1, True, k++, If[PalindromeQ[k] && AllTrue[Array[a, n-1], CoprimeQ[#, k]&], Return[k]]]; Array[a, 50] (* _Jean-François Alcover_, Jan 17 2018 *) %Y A083137 Cf. A002113, A083136, A083139 (primes in this sequence). %K A083137 base,nonn %O A083137 1,2 %A A083137 _Amarnath Murthy_ and Meenakshi Srikanth (menakan_s(AT)yahoo.com), Apr 24 2003 %E A083137 Corrected and extended by _Reinhard Zumkeller_, May 05 2003