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 A161988 #5 Jul 19 2015 10:23:41
%S A161988 1,33,560,6512,58343,429319,2701215,14938495,74085099,334526731,
%T A161988 1391777608,5386279880,19542335516,66903867676,217315477325,
%U A161988 672858527085,1993883448271,5674663272047,15558879389713,41208936343729
%N A161988 Number of reduced words of length n in the Weyl group B_33.
%C A161988 Computed with MAGMA using commands similar to those used to compute A161409.
%D A161988 J. E. Humphreys, Reflection Groups and Coxeter Groups, Cambridge, 1990. See under Poincaré polynomial.
%D A161988 N. Bourbaki, Groupes et alg. de Lie, Chap. 4, 5, 6. (The group is defined in Planche II.)
%F A161988 G.f. for B_m is the polynomial Prod_{k=1..m}(1-x^(2k))/(1-x). Only finitely many terms are nonzero. This is a row of the triangle in A128084.
%K A161988 nonn
%O A161988 0,2
%A A161988 _John Cannon_ and _N. J. A. Sloane_, Nov 30 2009