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 A162805 Number of reduced words of length n in Coxeter group on 19 generators S_i with relations (S_i)^2 = (S_i S_j)^3 = I. 0
 1, 19, 342, 5985, 104652, 1828503, 31947930, 558187605, 9752543136, 170394389307, 2977095147966, 52015183033833, 908798387526612, 15878335141888767, 277422946995884994, 4847075643050582301 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS The initial terms coincide with those of A170738, although the two sequences are eventually different. Computed with MAGMA using commands similar to those used to compute A154638. LINKS Index entries for linear recurrences with constant coefficients, signature (17, 17, -153). FORMULA G.f.: (t^3 + 2*t^2 + 2*t + 1)/(153*t^3 - 17*t^2 - 17*t + 1) MATHEMATICA CoefficientList[Series[(t^3+2*t^2+2*t+1)/(153*t^3-17*t^2-17*t+1), {t, 0, 30}], t] (* Harvey P. Dale, Aug 14 2011 *) CROSSREFS Sequence in context: A202043 A142549 A049629 * A049664 A163110 A163453 Adjacent sequences:  A162802 A162803 A162804 * A162806 A162807 A162808 KEYWORD nonn AUTHOR John Cannon and N. J. A. Sloane, Dec 03 2009 STATUS approved

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Last modified December 12 03:23 EST 2018. Contains 318052 sequences. (Running on oeis4.)