cp's OEIS Frontend

A170650 Number of reduced words of length n in Coxeter group on 17 generators S_i with relations (S_i)^2 = (S_i S_j)^49 = I.

%I A170650 #6 Nov 21 2016 11:19:22
%S A170650 1,17,272,4352,69632,1114112,17825792,285212672,4563402752,
%T A170650 73014444032,1168231104512,18691697672192,299067162755072,
%U A170650 4785074604081152,76561193665298432,1224979098644774912,19599665578316398592
%N A170650 Number of reduced words of length n in Coxeter group on 17 generators S_i with relations (S_i)^2 = (S_i S_j)^49 = I.
%C A170650 The initial terms coincide with those of A170736, although the two sequences are eventually different.
%C A170650 Computed with MAGMA using commands similar to those used to compute A154638.
%H A170650 <a href="/index/Rec#order_49">Index entries for linear recurrences with constant coefficients</a>, signature (15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, -120).
%F A170650 G.f. (t^49 + 2*t^48 + 2*t^47 + 2*t^46 + 2*t^45 + 2*t^44 + 2*t^43 + 2*t^42 +
%F A170650 2*t^41 + 2*t^40 + 2*t^39 + 2*t^38 + 2*t^37 + 2*t^36 + 2*t^35 + 2*t^34 +
%F A170650 2*t^33 + 2*t^32 + 2*t^31 + 2*t^30 + 2*t^29 + 2*t^28 + 2*t^27 + 2*t^26 +
%F A170650 2*t^25 + 2*t^24 + 2*t^23 + 2*t^22 + 2*t^21 + 2*t^20 + 2*t^19 + 2*t^18 +
%F A170650 2*t^17 + 2*t^16 + 2*t^15 + 2*t^14 + 2*t^13 + 2*t^12 + 2*t^11 + 2*t^10 +
%F A170650 2*t^9 + 2*t^8 + 2*t^7 + 2*t^6 + 2*t^5 + 2*t^4 + 2*t^3 + 2*t^2 + 2*t +
%F A170650 1)/(120*t^49 - 15*t^48 - 15*t^47 - 15*t^46 - 15*t^45 - 15*t^44 - 15*t^43
%F A170650 - 15*t^42 - 15*t^41 - 15*t^40 - 15*t^39 - 15*t^38 - 15*t^37 - 15*t^36 -
%F A170650 15*t^35 - 15*t^34 - 15*t^33 - 15*t^32 - 15*t^31 - 15*t^30 - 15*t^29 -
%F A170650 15*t^28 - 15*t^27 - 15*t^26 - 15*t^25 - 15*t^24 - 15*t^23 - 15*t^22 -
%F A170650 15*t^21 - 15*t^20 - 15*t^19 - 15*t^18 - 15*t^17 - 15*t^16 - 15*t^15 -
%F A170650 15*t^14 - 15*t^13 - 15*t^12 - 15*t^11 - 15*t^10 - 15*t^9 - 15*t^8 -
%F A170650 15*t^7 - 15*t^6 - 15*t^5 - 15*t^4 - 15*t^3 - 15*t^2 - 15*t + 1)
%K A170650 nonn
%O A170650 0,2
%A A170650 _John Cannon_ and _N. J. A. Sloane_, Dec 03 2009