162320domain: NAppears in sequencesa(n) = Sum_{k=1..n} (lcm(n,n-1,...,n-k+2,n-k+1)/lcm(1,2,...,k)).at n=19A093431Shifts 2 places left under Dirichlet convolution.at n=33A144366Number of 6-step one or two space at a time bishop's tours on an n X n board summed over all starting positions.at n=7A187050