Title of Paper: The hit problem for the Dickson algebra Author: Nguy\^{e}n H. V. Hung and Tran Ngoc Nam 2000 Mathematics Subject Classification: Primary 55S10, Secondary 55P47, 55Q45, 55T15. Address of authors: Department of Mathematics, Vietnam National University, Hanoi 334 Nguyen Trai Street, Hanoi, Vietnam E-mail address: nhvhung@vnu.edu.vn E-mail address: namtn@vnu.edu.vn Abstract: Let the mod 2 Steenrod algebra, ${\cal A}$, and the general linear group, $GL(k, F_2)$, act on $P_{k}:= F_2[x_{1},...,x_{k}]$ with $|x_{i}|=1$ in the usual manner. We prove the conjecture of the first-named author in {\it Spherical classes and the algebraic transfer}, (Trans. AMS 349 (1997), 3893-3910) stating that every element of positive degree in the Dickson algebra $D_{k}:=(P_{k})^{GL(k,F_2)}$ is ${\cal A}$-decomposable in $P_{k}$ for arbitrary $k>2$. This conjecture was shown to be equivalent to a weak algebraic version of the classical conjecture on spherical classes, which states that the only spherical classes in $Q_0S^0$ are the elements of Hopf invariant one and those of Kervaire invariant one.