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EltNewtonLift

Lifts an algebraic element with the Newton lifting method.

Syntax:

alpha := EltNewtonLift(o, a, f, p, k);

algebraic element
  alpha  
order
  o  
algebraic element
  a  
polynomial
  f  
integer
  p  
integer
  k  

Description:

Given an algebraic element a with f( a) \equiv 0 \bmod p o, this function calculates an algebraic element \alpha with f(\alpha) \equiv 0 \bmod p^{2^{ k}} o.


Example:


kash> o:=Order(Poly(Zx,[1,0,-4,0,1]));
Generating polynomial: x^4 - 4*x^2 + 1

kash> f:=Poly(Zx,[1,40,596,3920,9601]);
x^4 + 40*x^3 + 596*x^2 + 3920*x + 9601
kash> a:=Elt(o,[0,4,0,0]);
[0, 4, 0, 0]
kash> b:=EltNewtonLift(o,a,f,5,2);
[-10, -1, 0, 0]
kash> Eval(f, b);
> 0


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