2971433937domain: NAppears in sequencesNumber of (2+1)X(n+1) 0..3 arrays x(i,j) with row sums sum{x(i,j), j=1..n+1} nondecreasing, and column sums sum{i^2*x(i,j), i=1..2+1} nondecreasing.at n=6A233355