x_z3 := pAdicRing(3,20); x_z3x := PolynomialAlgebra(x_z3); x_f := 9*x_z3x.1^5+6*x_z3x.1^4+x_z3x.1^2+27*x_z3x.1+3; x_nf := NewtonPolygon(x_f); LowerVertices(x_nf);