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 A159712 #19 Jun 03 2018 07:56:13
%S A159712 0,0,0,0,0,0,0,0,2176,71424,1372160,20252672,255040512,2891180032,
%T A159712 30447656960,303926476800,2914762424320,27113686958080,
%U A159712 246327423270912,2196784154673152,19305427103907840,167673167523348480,1442534103145512960,12315082531044065280
%N A159712 Number of permutations of 1..n arranged in a circle with exactly 4 local maxima.
%H A159712 Alois P. Heinz, <a href="/A159712/b159712.txt">Table of n, a(n) for n = 0..1000</a>
%F A159712 G.f.: -128*(34560*x^7 -146880*x^6 +173712*x^5 -97304*x^4 +29808*x^3 -5120*x^2 +462*x-17)*x^8 / ((8*x-1)^2 *(6*x-1)^3 *(4*x-1)^4 *(2*x-1)^5). - _Alois P. Heinz_, Oct 26 2015
%t A159712 CoefficientList[Series[-128*(34560*x^7 -146880*x^6 +173712*x^5 -97304*x^4 +29808*x^3 -5120*x^2 +462*x-17)*x^8 / ((8*x-1)^2 *(6*x-1)^3 *(4*x-1)^4 *(2*x-1)^5), {x, 0, 50}], x] (* _G. C. Greubel_, Jun 02 2018 *)
%o A159712 (PARI) concat(vector(8), Vec(-128*(34560*x^7 -146880*x^6 +173712*x^5 -97304*x^4 +29808*x^3 -5120*x^2 +462*x-17)*x^8 / ((8*x-1)^2 *(6*x-1)^3 *(4*x-1)^4 *(2*x-1)^5) + O(x^100))) \\ _Altug Alkan_, Oct 26 2015
%Y A159712 Column k=4 of A263789.
%K A159712 nonn,easy
%O A159712 0,9
%A A159712 _R. H. Hardin_, Apr 20 2009
%E A159712 a(16)-a(23) from _Alois P. Heinz_, Oct 26 2015