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 A138073 #16 Feb 03 2023 04:55:01
%S A138073 1,1,6,1,1,6,1,6,1,1,6,1,8,1,6,1,1,6,1,8,0,8,1,6,1,1,6,1,8,0,3,0,8,1,
%T A138073 6,1,1,6,1,8,0,3,3,3,0,8,1,6,1,1,6,1,8,0,3,3,9,3,3,0,8,1,6,1,1,6,1,8,
%U A138073 0,3,3,9,8,9,3,3,0,8,1,6,1
%N A138073 Triangle read by rows: row n lists the digits of A135699(n), the palindromic number with odd number of digits formed from the reflected decimal expansion of golden ratio phi.
%C A138073 Also, successive digits of the terms of A135699.
%H A138073 G. C. Greubel, <a href="/A138073/b138073.txt">Table of n, a(n) for the first 50 rows</a>
%e A138073 Triangle begins:
%e A138073 .............. 1
%e A138073 ........... 1, 6, 1
%e A138073 ........ 1, 6, 1, 6, 1
%e A138073 ..... 1, 6, 1, 8, 1, 6, 1
%e A138073 .. 1, 6, 1, 8, 0, 8, 1, 6, 1
%t A138073 nn=10;With[{phi=RealDigits[GoldenRatio,10,nn+1][[1]]},Flatten[ Table[ Join[Take[phi,n],Take[phi,{n+1}],Reverse[Take[phi,n]]],{n,0,nn}]]] (* _Harvey P. Dale_, May 08 2012 *)
%Y A138073 Decimal expansion of phi: A001622. Cf. A135699, A135700, A138072.
%K A138073 easy,nonn,tabf,base
%O A138073 1,3
%A A138073 _Omar E. Pol_, Mar 03 2008