

A162381


Number of reduced words of length n in the Weyl group D_34.


0



1, 34, 594, 7106, 65449, 494768, 3195983, 18134478, 92219577, 426746308, 1818523916, 7204803796, 26747139312, 93651006988, 310966484313, 983825011398, 2977708459669, 8652371731716, 24211251121429, 65420187465158
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

0,2


COMMENTS

Computed with MAGMA using commands similar to those used to compute A161409.


REFERENCES

N. Bourbaki, Groupes et alg. de Lie, Chap. 4, 5, 6. (The group is defined in Planche IV.)
J. E. Humphreys, Reflection Groups and Coxeter Groups, Cambridge, 1990. See under PoincarĂ© polynomial.


LINKS

Table of n, a(n) for n=0..19.


FORMULA

G.f. for D_m is the polynomial f(n) * Product( f(2i), i=1..n1 )/ f(1)^n, where f(k) = 1x^k. Only finitely many terms are nonzero. This is a row of the triangle in A162206.


CROSSREFS

Sequence in context: A302955 A161647 A161991 * A010986 A232079 A264067
Adjacent sequences: A162378 A162379 A162380 * A162382 A162383 A162384


KEYWORD

nonn


AUTHOR

John Cannon and N. J. A. Sloane, Dec 01 2009


STATUS

approved



