3979200domain: NAppears in sequencesa(n) = n^2*(n+1)^2*(4*n^2 - 5*n + 4)/12.at n=15A101381Number of -3..3 arrays x(i) of n+1 elements i=1..n+1 with set{t,u,v in 0,1}((x[i+t]+x[j+u]+x[k+v])*(-1)^(t+u+v)) having four or six distinct values for every i,j,k<=n.at n=11A211728