Module

BoundedCyclotomicExponent.lean

Nyll.ValuedFieldTheory.Valuation.BoundedCyclotomicExponent
1 declaration indexed from sourceView source ↗

The p-adic order of a bounded cyclotomic exponent

If a natural exponent below p^(s+1) differs from one, its difference from one is nonzero and has p-adic order below s+1. The absolute value of that integer is strictly below the modulus, so divisibility by the modulus is impossible. The exponent zero and the prime two are included.

Imports3
  • Mathlib.NumberTheory.Padics.PadicVal.Basic
  • Mathlib.Data.Int.Basic
  • Mathlib.Algebra.Order.GroupWithZero.Basic
Imported by2

Declarations

ValuationTheory.one_sub_natCast_ne_zero_and_padicValInt_lt

A bounded exponent different from one has nonzero difference from one and p-adic order strictly below the selected prime-power level.

Source context 1 command

Surrounding namespaces, section variables, and local commands at this declaration.

namespace ValuationTheory
theorem one_sub_natCast_ne_zero_and_padicValInt_lt
    (p a s : ℕ) [Fact p.Prime]
    (ha : a < p ^ (s + 1)) (ha1 : a ≠ 1) :
    1 - (a : ℤ) ≠ 0 ∧ padicValInt p (1 - (a : ℤ)) < s + 1