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 A159714 #15 Oct 26 2015 14:14:50 %S A159714 0,0,0,0,0,0,0,0,0,0,0,0,4245504,290787328,11134212096,315250053120, %T A159714 7373732315136,151048265662464,2807359026757632,48456016702472192, %U A159714 789426139189739520,12282937010848530432,184138764390344687616,2677761622120892203008 %N A159714 Number of permutations of 1..n arranged in a circle with exactly 6 local maxima. %H A159714 Alois P. Heinz, <a href="/A159714/b159714.txt">Table of n, a(n) for n = 0..930</a> %F A159714 G.f.: -2048*(24078974976000*x^16 -163737029836800*x^15 +392749501317120*x^14 -517950785912832*x^13 +442017305468928*x^12 -264568164065280*x^11 +116194714660608*x^10 -38443271058176*x^9 +9722233013888*x^8 -1890674565824*x^7 +282315254112*x^6 -32071886064*x^5 +2720304072*x^4 -166678732*x^3 +6962515*x^2 -177256*x +2073)*x^12 / ((12*x-1)^2 *(10*x-1)^3 *(8*x-1)^4 *(6*x-1)^5 *(4*x-1)^6 *(2*x-1)^7). - _Alois P. Heinz_, Oct 26 2015 %o A159714 (PARI) concat(vector(12), Vec(-2048*(24078974976000*x^16 -163737029836800*x^15 +392749501317120*x^14 -517950785912832*x^13 +442017305468928*x^12 -264568164065280*x^11 +116194714660608*x^10 -38443271058176*x^9 +9722233013888*x^8 -1890674565824*x^7 +282315254112*x^6 -32071886064*x^5 +2720304072*x^4 -166678732*x^3 +6962515*x^2 -177256*x +2073)*x^12 / ((12*x-1)^2 *(10*x-1)^3 *(8*x-1)^4 *(6*x-1)^5 *(4*x-1)^6 *(2*x-1)^7) + O(x^100))) \\ _Altug Alkan_, Oct 26 2015 %Y A159714 Column k=6 of A263789. %K A159714 nonn,easy %O A159714 0,13 %A A159714 _R. H. Hardin_, Apr 20 2009 %E A159714 a(17)-a(23) from _Alois P. Heinz_, Oct 26 2015