187112domain: NAppears in sequencesA(x) satisfies A000290(x)/x^2 = A(x)/A(x^2); A000290 = integer squares.at n=21A173277Number of nX3 0..1 arrays with every element unequal to 0, 2, 3, 4, 6 or 7 king-move adjacent elements, with upper left element zero.at n=9A306131