cp's OEIS Frontend

A170454 Number of reduced words of length n in Coxeter group on 13 generators S_i with relations (S_i)^2 = (S_i S_j)^45 = I.

%I A170454 #8 Jan 20 2019 13:15:18
%S A170454 1,13,156,1872,22464,269568,3234816,38817792,465813504,5589762048,
%T A170454 67077144576,804925734912,9659108818944,115909305827328,
%U A170454 1390911669927936,16690940039135232,200291280469622784
%N A170454 Number of reduced words of length n in Coxeter group on 13 generators S_i with relations (S_i)^2 = (S_i S_j)^45 = I.
%C A170454 The initial terms coincide with those of A170732, although the two sequences are eventually different.
%C A170454 Computed with MAGMA using commands similar to those used to compute A154638.
%H A170454 <a href="/index/Rec#order_45">Index entries for linear recurrences with constant coefficients</a>, signature (11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, -66).
%F A170454 G.f. (t^45 + 2*t^44 + 2*t^43 + 2*t^42 + 2*t^41 + 2*t^40 + 2*t^39 + 2*t^38 +
%F A170454 2*t^37 + 2*t^36 + 2*t^35 + 2*t^34 + 2*t^33 + 2*t^32 + 2*t^31 + 2*t^30 +
%F A170454 2*t^29 + 2*t^28 + 2*t^27 + 2*t^26 + 2*t^25 + 2*t^24 + 2*t^23 + 2*t^22 +
%F A170454 2*t^21 + 2*t^20 + 2*t^19 + 2*t^18 + 2*t^17 + 2*t^16 + 2*t^15 + 2*t^14 +
%F A170454 2*t^13 + 2*t^12 + 2*t^11 + 2*t^10 + 2*t^9 + 2*t^8 + 2*t^7 + 2*t^6 +
%F A170454 2*t^5 + 2*t^4 + 2*t^3 + 2*t^2 + 2*t + 1)/(66*t^45 - 11*t^44 - 11*t^43 -
%F A170454 11*t^42 - 11*t^41 - 11*t^40 - 11*t^39 - 11*t^38 - 11*t^37 - 11*t^36 -
%F A170454 11*t^35 - 11*t^34 - 11*t^33 - 11*t^32 - 11*t^31 - 11*t^30 - 11*t^29 -
%F A170454 11*t^28 - 11*t^27 - 11*t^26 - 11*t^25 - 11*t^24 - 11*t^23 - 11*t^22 -
%F A170454 11*t^21 - 11*t^20 - 11*t^19 - 11*t^18 - 11*t^17 - 11*t^16 - 11*t^15 -
%F A170454 11*t^14 - 11*t^13 - 11*t^12 - 11*t^11 - 11*t^10 - 11*t^9 - 11*t^8 -
%F A170454 11*t^7 - 11*t^6 - 11*t^5 - 11*t^4 - 11*t^3 - 11*t^2 - 11*t + 1)
%t A170454 coxG[{45,66,-11}] (* The coxG program is at A169452 *) (* _Harvey P. Dale_, Jan 20 2019 *)
%K A170454 nonn
%O A170454 0,2
%A A170454 _John Cannon_ and _N. J. A. Sloane_, Dec 03 2009