Ramification of automorphisms of k((t))

[摘要] Let k be a field of characteristic p and let gamma is an element of Aut(k)(k((t))). For m greater than or equal to 0 define i(m) = v(r)(gamma(Pm)t - t) - 1. We show that if p inverted iota i(0) is and i(1) (p(2) - p + 1) i(o) then there exists an integer b such that i(m) = i(0) + bp + bp(2) + bp(m) for all m greater than or equal to 1. (C) 1997 Academic Press.

[发布日期] 1997-03-01