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 A167289 #32 May 27 2024 11:40:46 %S A167289 1,2,1,3,2,1,4,3,2,1,5,4,3,2,1,6,5,4,3,2,1,7,6,5,4,3,2,8,1,7,6,5,4,3, %T A167289 9,2,8,1,7,6,5,4,10,3,9,2,8,1,7,6,5,11,4,10,3,9,2,8,1,7,6,12,5,11,4, %U A167289 10,3,9,2,8,1,7,13,6,12,5,11,4,10,3,9,2,8,14,1,7,13,6,12,5,11,4,10,3,9,15 %N A167289 Signature sequence of the smallest Salem number of degree 18 (A219300). %H A167289 G. C. Greubel, <a href="/A167289/b167289.txt">Table of n, a(n) for n = 1..5000</a> %H A167289 Michael Mossinghoff, <a href="http://wayback.cecm.sfu.ca/~mjm/Lehmer/">Lehmer's Problem Website</a>. %H A167289 Michael Mossinghoff, <a href="http://wayback.cecm.sfu.ca/~mjm/Lehmer/lists/SalemList.html">Small Salem Numbers</a>. %H A167289 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/SignatureSequence.html">Signature Sequence</a>. %H A167289 <a href="/index/Si#signature_sequences">Index entries for sequences related to signature sequences</a> %t A167289 a = {1, -1, 1, -1, 0, 0, -1, 1, -1}; %t A167289 b = Join[a, {1}, Reverse[a]]; %t A167289 p[x_] = Sum[b[[n]]*x^(n - 1), {n, 1, Length[b]}]; %t A167289 m = Root[p[x], 2]; %t A167289 Take[Transpose[Sort[Flatten[Table[{i + j*m, i}, {i, 25}, {j, 17}], 1], #1[[1]] < #2[[1]] &]][[2]], 95] %Y A167289 Cf. A073011, A147851, A219300. %K A167289 nonn,less %O A167289 1,2 %A A167289 _Roger L. Bagula_, Nov 01 2009