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 A371183 #7 Mar 23 2024 20:30:58
%S A371183 1,2,4,3,8,9,22,5,6,21,20,10,7,17,71,70,12,23,24,14,25,26,13,31,30,15,
%T A371183 51,50,16,27,28,18,29,32,33,19,34,38,39,42,52,41,40,100,102,103,104,
%U A371183 105,106,107,108,109,130,120,122,54,43,35,36,53,37,62,55,44,56,45,46,58,47,48
%N A371183 Lexicographically earliest sequence of distinct terms in which every triple of consecutive digits contains only one pair that is not coprime.
%t A371183 pairwiseQ[a_,b_,c_]:=Sort[{CoprimeQ[a,b],CoprimeQ[b,c],CoprimeQ[a,c]}]=={False,True,True}; a[1]=1;a[2]=2;a[3]=4;
%t A371183 a[n_]:=a[n]=Module[{k=1,digits,tab=Table[a[i],{i,1,n-1}]},
%t A371183 While[digits=Join[Take[Flatten[IntegerDigits[Take[tab,-3]]],-3],IntegerDigits[k]];
%t A371183 MemberQ[tab,k]||Union[pairwiseQ@@@
%t A371183 Table[{digits[[i]],digits[[i+1]],digits[[i+2]]},
%t A371183 {i,1,Length[digits]-2}]]!={True},k++];k]; a/@Range[70]
%Y A371183 Cf. A353187, A371060, A371182.
%K A371183 nonn,base
%O A371183 1,2
%A A371183 _Ivan N. Ianakiev_, Mar 14 2024