%I #5 Jul 19 2015 10:32:20

%S 1,27,377,3626,26999,165852,874755,4071079,17052724,65259715,

%T 230856472,761987905,2364726003,6943746516,19395654894,51770913911,

%U 132567002957,326758146932,777583981286,1791153918119,4003030425506,8697839966552

%N Number of reduced words of length n in the Weyl group A_27.

%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 I.)

%F G.f. for A_m is the polynomial Prod_{k=1..m}(1-x^(k+1))/(1-x). Only finitely many terms are nonzero. This is a row of the triangle in A008302.

%K nonn

%O 0,2

%A _John Cannon_ and _N. J. A. Sloane_, Nov 30 2009