

A165726


Number of reduced words of length n in Coxeter group on 50 generators S_i with relations (S_i)^2 = (S_i S_j)^9 = I.


0



1, 50, 2450, 120050, 5882450, 288240050, 14123762450, 692064360050, 33911153642450, 1661646528478825, 81420679895402400, 3989613314871777600, 195491052428573042400, 9579061568993020137600, 469374016880312098682400
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OFFSET

0,2


COMMENTS

The initial terms coincide with those of A170769, although the two sequences are eventually different.
Computed with MAGMA using commands similar to those used to compute A154638.


LINKS

Table of n, a(n) for n=0..14.
Index entries for linear recurrences with constant coefficients, signature (48, 48, 48, 48, 48, 48, 48, 48, 1176).


FORMULA

G.f. (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 +
1)/(1176*t^9  48*t^8  48*t^7  48*t^6  48*t^5  48*t^4  48*t^3 
48*t^2  48*t + 1)


CROSSREFS

Sequence in context: A164351 A164695 A165182 * A166325 A166463 A166856
Adjacent sequences: A165723 A165724 A165725 * A165727 A165728 A165729


KEYWORD

nonn


AUTHOR

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


STATUS

approved



