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 A127203 #22 Sep 19 2024 21:59:06
%S A127203 1,2,1,3,1,5,1,7,2,1,3,1,11,1,13,1,3,2,1,17,1,19,2,1,3,1,23,1,5,3,1,4,
%T A127203 1,29,1,31,1,3,1,5,1,37,1,3,1,41,1,43,2,1,3,1,47,1,7,2,1,3,2,1,53,1,5,
%U A127203 3,1,59,1,61,1,3,2,1,5,1,67,2,1,3,1,71,1,73,1,3,2,1,7,1,79,2,1,3,1,83,1,5,2
%N A127203 a(n) = gcd(A127202(n), A127202(n+1)).
%C A127203 a(n) never equals a(n+1), by decree.
%C A127203 For the first 719 terms this coincides with the sequence {gcd(A280985(n), A280985(n+1))}. By decree, the latter may not contain two consecutive 1's. - _N. J. A. Sloane_, Jan 21 2017
%H A127203 Rémy Sigrist, <a href="/A127203/b127203.txt">Table of n, a(n) for n = 1..10000</a>
%t A127203 f[l_List] := Block[{k = 1, c = GCD[l[[ -1]], l[[ -2]]]},While[MemberQ[l, k] || GCD[k, l[[ -1]]] == c, k++ ];Append[l, k]]; GCD @@@ Partition[Nest[f, {1, 2}, 100], 2, 1] (* _Ray Chandler_, Jan 16 2007 *)
%Y A127203 Cf. A127202, A280985.
%K A127203 nonn
%O A127203 1,2
%A A127203 _Leroy Quet_, Jan 08 2007
%E A127203 Extended by _Ray Chandler_, Jan 16 2007