898670domain: NAppears in sequencesNumbers k such that k and k^2 use only the digits 0, 6, 7, 8 and 9.at n=19A136966Number of walks within N^2 (the first quadrant of Z^2) starting at (0,0), ending on the vertical axis and consisting of n steps taken from {(-1, -1), (0, 1), (1, 0)}.at n=17A151376