cp's OEIS Frontend

A170199 Number of reduced words of length n in Coxeter group on 46 generators S_i with relations (S_i)^2 = (S_i S_j)^39 = I.

%I A170199 #8 Jun 01 2017 10:35:23
%S A170199 1,46,2070,93150,4191750,188628750,8488293750,381973218750,
%T A170199 17188794843750,773495767968750,34807309558593750,1566328930136718750,
%U A170199 70484801856152343750,3171816083526855468750,142731723758708496093750
%N A170199 Number of reduced words of length n in Coxeter group on 46 generators S_i with relations (S_i)^2 = (S_i S_j)^39 = I.
%C A170199 The initial terms coincide with those of A170765, although the two sequences are eventually different.
%C A170199 Computed with MAGMA using commands similar to those used to compute A154638.
%H A170199 <a href="/index/Rec#order_39">Index entries for linear recurrences with constant coefficients</a>, signature (44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, -990).
%F A170199 G.f. (t^39 + 2*t^38 + 2*t^37 + 2*t^36 + 2*t^35 + 2*t^34 + 2*t^33 + 2*t^32 +
%F A170199 2*t^31 + 2*t^30 + 2*t^29 + 2*t^28 + 2*t^27 + 2*t^26 + 2*t^25 + 2*t^24 +
%F A170199 2*t^23 + 2*t^22 + 2*t^21 + 2*t^20 + 2*t^19 + 2*t^18 + 2*t^17 + 2*t^16 +
%F A170199 2*t^15 + 2*t^14 + 2*t^13 + 2*t^12 + 2*t^11 + 2*t^10 + 2*t^9 + 2*t^8 +
%F A170199 2*t^7 + 2*t^6 + 2*t^5 + 2*t^4 + 2*t^3 + 2*t^2 + 2*t + 1)/(990*t^39 -
%F A170199 44*t^38 - 44*t^37 - 44*t^36 - 44*t^35 - 44*t^34 - 44*t^33 - 44*t^32 -
%F A170199 44*t^31 - 44*t^30 - 44*t^29 - 44*t^28 - 44*t^27 - 44*t^26 - 44*t^25 -
%F A170199 44*t^24 - 44*t^23 - 44*t^22 - 44*t^21 - 44*t^20 - 44*t^19 - 44*t^18 -
%F A170199 44*t^17 - 44*t^16 - 44*t^15 - 44*t^14 - 44*t^13 - 44*t^12 - 44*t^11 -
%F A170199 44*t^10 - 44*t^9 - 44*t^8 - 44*t^7 - 44*t^6 - 44*t^5 - 44*t^4 - 44*t^3 -
%F A170199 44*t^2 - 44*t + 1)
%t A170199 coxG[{39,990,-44}] (* The coxG program is at A169452 *) (* _Harvey P. Dale_, Jun 01 2017 *)
%K A170199 nonn
%O A170199 0,2
%A A170199 _John Cannon_ and _N. J. A. Sloane_, Dec 03 2009