284546domain: NAppears in sequencesFirst row of infinite array A(j,k): A(j,1) = j-1; A(1,k) = A(2,k-1); for j, k > 1, A(j,k) = A(j-1,k) - A(j+1,k-1) if that number is positive and not already in column k, A(j,k) = A(j-1,k) + A(j+1,k-1) otherwise.at n=27A140985