138419domain: NAppears in sequencesNumber of (2+1) X (n+1) arrays of permutations of 0..n*3+2 with each element having directed index change 0,1 2,2 1,0 -1,2 -2,-1 or -1,-1.at n=10A264423a(n) = Sum_{k=1..n} k^2*tau_3(k), where tau_3 is A007425.at n=31A319088