Number of reduced words of length n in Coxeter group on 20 generators S_i with relations (S_i)^2 = (S_i S_j)^7 = I.

A164633

Number of reduced words of length n in Coxeter group on 20 generators S_i with relations (S_i)^2 = (S_i S_j)^7 = I.

Terms

    a(0) =1a(1) =20a(2) =380a(3) =7220a(4) =137180a(5) =2606420a(6) =49521980a(7) =940917430a(8) =17877427560a(9) =339671055240

External references