1941660

Appears in sequences

• Number of reduced words of length n in Coxeter group on 7 generators S_i with relations (S_i)^2 = (S_i S_j)^5 = I.at n=8A163345
• a(n) = 3*(n + 1)*(n + 2)*(3*n + 1)*(3*n + 4)/4.at n=22A268685