Every sum of cubes in F2[t] is a strict sum of 6 cubes

It is easy to see that an element P(t) F2[t] is a sum of cubes if and only if We say that P(t) is a “strict” sum of cubes A1(t)3+ +Ag(t)3 if we have for each i, and we define g(3,F2[t]) as the least g such that every element of M(2) is a strict sum of g cubes. Our main result is then that5 g(3,F2[t]) 6. This improves on a recent result 4 g(3,F2[t]) 9 of the first named author.