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%I #9 Apr 01 2017 07:11:00
%S 1,16,135,800,3739,14672,50252,154224,432174,1121456,2724183,6248128,
%T 13624922,28409312,56910017,109964720,205651975,373334400,659553555,
%U 1136450288,1913567669,3154109024,5096972454,8086166144,12609525259
%N Number of reduced words of length n in the Weyl group B_16.
%C Computed with MAGMA using commands similar to those used to compute A161409.
%D J. E. Humphreys, Reflection Groups and Coxeter Groups, Cambridge, 1990. See under Poincaré polynomial.
%D N. Bourbaki, Groupes et alg. de Lie, Chap. 4, 5, 6. (The group is defined in Planche II.)
%H Robert Israel, <a href="/A161876/b161876.txt">Table of n, a(n) for n = 0..256</a> (complete sequence)
%F 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.
%p G:= normal(mul((1-x^(2*k))/(1-x),k=1..16)):
%p seq(coeff(G,x,j),j=0..256); # _Robert Israel_, Mar 31 2017
%K nonn,fini,full
%O 0,2
%A _John Cannon_ and _N. J. A. Sloane_, Nov 30 2009
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