61394domain: NAppears in sequencesCoefficient of x in the reduction by x^2->x+1 of the polynomial p(n,x) defined below in Comments.at n=18A192755Number of (7+1) X (n+1) 0..1 arrays with every 2 X 2 subblock ne-sw antidiagonal difference nondecreasing horizontally and nw+se diagonal sum nondecreasing vertically.at n=13A258560