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 A135699 #6 Oct 27 2016 03:17:35
%S A135699 1,161,16161,1618161,161808161,16180308161,1618033308161,
%T A135699 161803393308161,16180339893308161,1618033988893308161,
%U A135699 161803398878893308161,16180339887478893308161
%N A135699 Palindromes with odd number of digits formed from the reflected decimal expansion of golden ratio phi.
%C A135699 Phi = 1.61803398874989484820458683436... (see A001622).
%C A135699 The number of digits of a(n) is equal to 2n - 1.
%H A135699 G. C. Greubel, <a href="/A135699/b135699.txt">Table of n, a(n) for n = 1..250</a>
%e A135699 n ............ a(n)
%e A135699 1 ............. 1
%e A135699 2 ............ 161
%e A135699 3 ........... 16161
%e A135699 4 .......... 1618161
%e A135699 5 ......... 161808161
%e A135699 6 ........ 16180308161
%e A135699 7 ....... 1618033308161
%e A135699 8 ...... 161803393308161
%e A135699 9 ..... 16180339893308161
%e A135699 10 ... 1618033988893308161
%t A135699 With[{ed = RealDigits[(1 + Sqrt[5])/2, 10, 25][[1]]}, Table[FromDigits[Join[Take[ed, n], Reverse[Take[ed, n - 1]]]], {n,25}]] (* _G. C. Greubel_, Oct 27 2016 *)
%Y A135699 Cf. A001622, A002113.
%K A135699 base,nonn
%O A135699 1,2
%A A135699 _Omar E. Pol_, Mar 01 2008