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 A244888 #10 Nov 24 2018 08:15:00 %S A244888 1,-2,1,6,-6,1,-23,36,-15,1,106,-229,160,-37,1,-567,1574,-1566,650, %T A244888 -93,1,3434,-11706,15248,-9310,2572,-238,1,-23137,93831,-151933, %U A244888 123814,-52136,10175,-616,1 %N A244888 Triangle of coefficients arising in study of up-down permutations. %C A244888 See Remmel (2014) for precise definition. %H A244888 Jeffrey B. Remmel, <a href="http://www.combinatorics.org/ojs/index.php/eljc/article/view/v21i3p2">Consecutive Up-down Patterns in Up-down Permutations</a>, Electron. J. Combin., 21 (2014), #P3.2. See p. 25. %e A244888 Triangle begins: %e A244888 1; %e A244888 -2, 1; %e A244888 6, -6, 1; %e A244888 -23, 36, -15, 1; %e A244888 106, -229, 160, -37, 1; %e A244888 -567, 1574, -1566, 650, -93, 1; %e A244888 3434, -11706, 15248, -9310, 2572, -238, 1; %e A244888 -23137, 93831, -151933, 123814, -52136, 10175, -616, 1; %e A244888 ... %Y A244888 First two columns are A125273 and A244889. %K A244888 sign,tabl %O A244888 1,2 %A A244888 _N. J. A. Sloane_, Jul 12 2014