Documentation

Init.Data.Int.DivMod.Bootstrap

Lemmas about integer division needed to bootstrap omega. #

dvd #

theorem Int.dvd_def (a b : Int) :
(a b) = (c : Int), b = a * c
@[simp]
theorem Int.dvd_zero (n : Int) :
n 0
@[simp]
theorem Int.dvd_refl (n : Int) :
n n
@[simp]
theorem Int.one_dvd (n : Int) :
1 n
theorem Int.dvd_trans {a b c : Int} :
a bb ca c
theorem Int.ofNat_dvd {m n : Nat} :
m n m n
@[simp]
theorem Int.zero_dvd {n : Int} :
0 n n = 0
theorem Int.dvd_mul_right (a b : Int) :
a a * b
theorem Int.dvd_mul_left (a b : Int) :
b a * b
@[simp]
theorem Int.neg_dvd {a b : Int} :
-a b a b
@[simp]
theorem Int.dvd_neg {a b : Int} :
a -b a b
@[simp]
theorem Int.natAbs_dvd_natAbs {a b : Int} :
theorem Int.ofNat_dvd_left {n : Nat} {z : Int} :
n z n z.natAbs

ediv zero #

@[simp]
theorem Int.zero_ediv (b : Int) :
0 / b = 0
@[simp]
theorem Int.ediv_zero (a : Int) :
a / 0 = 0

emod zero #

@[simp]
theorem Int.zero_emod (b : Int) :
0 % b = 0
@[simp]
theorem Int.emod_zero (a : Int) :
a % 0 = a

ofNat mod #

@[simp]
theorem Int.ofNat_emod (m n : Nat) :
↑(m % n) = m % n

mod definitions #

theorem Int.emod_add_ediv (a b : Int) :
a % b + b * (a / b) = a
theorem Int.emod_add_ediv.aux (m n : Nat) :
n - (m % n + 1) - (n * (m / n) + n) = negSucc m
theorem Int.emod_add_ediv' (a b : Int) :
a % b + a / b * b = a

Variant of emod_add_ediv with the multiplication written the other way around.

theorem Int.ediv_add_emod (a b : Int) :
b * (a / b) + a % b = a
theorem Int.ediv_add_emod' (a b : Int) :
a / b * b + a % b = a

Variant of ediv_add_emod with the multiplication written the other way around.

theorem Int.emod_def (a b : Int) :
a % b = a - b * (a / b)

/ ediv #

@[simp]
theorem Int.ediv_neg (a b : Int) :
a / -b = -(a / b)
theorem Int.div_def (a b : Int) :
a / b = a.ediv b
theorem Int.add_mul_ediv_right (a b : Int) {c : Int} (H : c 0) :
(a + b * c) / c = a / c + b
theorem Int.add_mul_ediv_left (a : Int) {b : Int} (c : Int) (H : b 0) :
(a + b * c) / b = a / b + c
theorem Int.add_ediv_of_dvd_right {a b c : Int} (H : c b) :
(a + b) / c = a / c + b / c
theorem Int.add_ediv_of_dvd_left {a b c : Int} (H : c a) :
(a + b) / c = a / c + b / c
@[simp]
theorem Int.mul_ediv_cancel (a : Int) {b : Int} (H : b 0) :
a * b / b = a
@[simp]
theorem Int.mul_ediv_cancel_left {a : Int} (b : Int) (H : a 0) :
a * b / a = b
theorem Int.ediv_nonneg_iff_of_pos {a b : Int} (h : 0 < b) :
0 a / b 0 a
@[reducible, inline, deprecated Int.ediv_nonneg_iff_of_pos (since := "2025-02-28")]
abbrev Int.div_nonneg_iff_of_pos {a b : Int} (h : 0 < b) :
0 a / b 0 a
Equations

emod #

theorem Int.emod_nonneg (a : Int) {b : Int} :
b 00 a % b
theorem Int.emod_lt_of_pos (a : Int) {b : Int} (H : 0 < b) :
a % b < b
@[simp]
theorem Int.add_mul_emod_self {a b c : Int} :
(a + b * c) % c = a % c
@[simp]
theorem Int.add_mul_emod_self_left (a b c : Int) :
(a + b * c) % b = a % b
@[simp]
theorem Int.emod_add_emod (m n k : Int) :
(m % n + k) % n = (m + k) % n
@[simp]
theorem Int.add_emod_emod (m n k : Int) :
(m + n % k) % k = (m + n) % k
theorem Int.add_emod (a b n : Int) :
(a + b) % n = (a % n + b % n) % n
theorem Int.add_emod_eq_add_emod_right {m n k : Int} (i : Int) (H : m % n = k % n) :
(m + i) % n = (k + i) % n
theorem Int.emod_add_cancel_right {m n k : Int} (i : Int) :
(m + i) % n = (k + i) % n m % n = k % n
@[simp]
theorem Int.mul_emod_left (a b : Int) :
a * b % b = 0
@[simp]
theorem Int.mul_emod_right (a b : Int) :
a * b % a = 0
theorem Int.mul_emod (a b n : Int) :
a * b % n = a % n * (b % n) % n
@[simp]
theorem Int.emod_self {a : Int} :
a % a = 0
@[simp]
theorem Int.emod_emod_of_dvd (n : Int) {m k : Int} (h : m k) :
n % k % m = n % m
@[simp]
theorem Int.emod_emod (a b : Int) :
a % b % b = a % b
theorem Int.sub_emod (a b n : Int) :
(a - b) % n = (a % n - b % n) % n

properties of / and % #

theorem Int.mul_ediv_cancel_of_emod_eq_zero {a b : Int} (H : a % b = 0) :
b * (a / b) = a
theorem Int.ediv_mul_cancel_of_emod_eq_zero {a b : Int} (H : a % b = 0) :
a / b * b = a
theorem Int.dvd_of_emod_eq_zero {a b : Int} (H : b % a = 0) :
a b
theorem Int.emod_eq_zero_of_dvd {a b : Int} :
a bb % a = 0
theorem Int.dvd_iff_emod_eq_zero {a b : Int} :
a b b % a = 0
theorem Int.mul_ediv_assoc (a : Int) {b c : Int} :
c ba * b / c = a * (b / c)
theorem Int.mul_ediv_assoc' (b : Int) {a c : Int} (h : c a) :
a * b / c = a / c * b
theorem Int.neg_ediv_of_dvd {a b : Int} :
b a-a / b = -(a / b)
theorem Int.sub_ediv_of_dvd (a : Int) {b c : Int} (hcb : c b) :
(a - b) / c = a / c - b / c
theorem Int.ediv_mul_cancel {a b : Int} (H : b a) :
a / b * b = a
theorem Int.mul_ediv_cancel' {a b : Int} (H : a b) :
a * (b / a) = b
theorem Int.emod_pos_of_not_dvd {a b : Int} (h : ¬a b) :
a = 0 0 < b % a

/ and ordering #

theorem Int.mul_ediv_self_le {x k : Int} (h : k 0) :
k * (x / k) x
theorem Int.lt_mul_ediv_self_add {x k : Int} (h : 0 < k) :
x < k * (x / k) + k

bmod #

@[simp]
theorem Int.bmod_emod {x : Int} {m : Nat} :
x.bmod m % m = x % m
theorem Int.bmod_def (x : Int) (m : Nat) :
x.bmod m = if x % m < (m + 1) / 2 then x % m else x % m - m