82620domain: NAppears in sequencesNumbers k such that k and k^2 use only the digits 0, 2, 4, 6 and 8.at n=43A136904G.f. A(x) satisfies: 6*A(x) = A(A(A(A(A(x))))) + 5*x + x^2 with A(0)=0.at n=4A138915Number of integer compositions of n whose leaders of maximal strictly increasing runs are not weakly decreasing.at n=18A375135