(1+u+u2)-cyclic codes over F2+uF2+u2F2
环F2+uF2+u2F2上的(1+u+u2）—循环码*

This paper defined a new Gray map between codes over F2+uF2+u2F2 and codes over F2. By means of this map, it shown that the Gray image of a linear (1+u+u2)-cyclic code over F2+uF2+u2F2 is a binary-distance-invariant linear cyclic code. Furthermore, if n=3(mod 4), obtained the generator polynomial of the Gray images of (1+u+u2)-cyclic codes. It is significant to construct new good codes.