An ordered additive commutative monoid is called archimedean
if for any two elements x
, y
such that 0 < y
there exists a natural number n
such that x ≤ n •ℕ y
.
Every x greater than or equal to 1 is between two successive natural-number powers of every y greater than one.
Every positive x is between two successive integer powers of
another y greater than one. This is the same as exists_int_pow_near'
,
but with ≤ and < the other way around.
Every positive x is between two successive integer powers of
another y greater than one. This is the same as exists_int_pow_near
,
but with ≤ and < the other way around.
A linear ordered archimedean ring is a floor ring. This is not an instance
because in some
cases we have a computable floor
function.
Equations
- archimedean.floor_ring α = {floor := λ (x : α), classical.some _, le_floor := _}