A164959 Number of reduced words of length n in Coxeter group on 24 generators S_i with relations (S_i)^2 = (S_i S_j)^8 = I.

1, 24, 552, 12696, 292008, 6716184, 154472232, 3552861336, 81715810452, 1879463634048, 43227663437376, 994236255707904, 22867433804191680, 525950975723336064, 12096872400856060224, 278228064281733992448

Offset: 0

Author

John Cannon and N. J. A. Sloane, Dec 03 2009

Keywords

• nonn

Comments

The initial terms coincide with those of A170743, 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 (22, 22, 22, 22, 22, 22, 22, -253).

Programs

Mathematica

coxG[{8,253,-22}] (* The coxG program is at A169452 *) (* Harvey P. Dale, Mar 20 2023 *)

Formula

G.f. (t^8 + 2*t^7 + 2*t^6 + 2*t^5 + 2*t^4 + 2*t^3 + 2*t^2 + 2*t + 1)/(253*t^8 -

22*t^7 - 22*t^6 - 22*t^5 - 22*t^4 - 22*t^3 - 22*t^2 - 22*t + 1)