Documentation

Marginis.KjosHanssen2010

Permutations of the integers induce only the trivial automorphism of the Turing degrees #

by Kjos-Hanssen, Bjørn

https://arxiv.org/pdf/1408.2850.pdf

theorem page5_display3_equals2 (b : ) :
2 ^ (b + 1) * 4 ^ (b - 1) = 2 ^ (3 * b - 1)

https://arxiv.org/pdf/1408.2850.pdf Page 5 3rd displayed equation Second "equals" sign

theorem page7_display4_lt2 (b : ) (c : ) (h : b < c) :
2 ^ (-b) + 2 ^ (-c) < 2 ^ (-(b - 1))

https://arxiv.org/pdf/1408.2850.pdf Page 7 4th displayed equation Second "<" sign

theorem bound_of_nonneg (p : ) :
0 4 * p * (p - 1) + 1
theorem numerator_bound (p : ) :
4 * (p * (1 - p)) 1
theorem le_div {a : } {b : } {c : } (ha : 0 < a) (g : a * b c) :
b c / a
theorem the_bound (p : ) :
p * (1 - p) 1 / 4
theorem mul_self_bound {p : } (h0 : 0 p) (h1 : p 1) :
p * p 1
theorem sq_bound {p : } (h0 : 0 p) (h1 : p 1) :
p ^ 2 1
theorem cube_bound {p : } (h0 : 0 p) (h1 : p 1) :
p ^ 3 1
theorem cube_bound' {p : } (h0 : 0 p) (h1 : p 1) :
(1 - p) ^ 3 1
theorem paper_bound {p : } (h0 : 0 p) (h1 : p 1) :
(1 - p) ^ 3 + p ^ 3 2
theorem paper_bound' {p : } (h0 : 0 p) (h1 : p 1) :
p * (1 - p) * ((1 - p) ^ 3 + p ^ 3) 1 / 2
theorem paper_bound'' {p : } (h0 : 0 p) (h1 : p 1) :
(1 - p) ^ 4 * p + p ^ 4 * (1 - p) 1 / 2

Page 8 5th displayed equation Inequality

theorem choose_two (n : ) :
2 * n.choose 2 = n * (n - 1)
theorem page7_bottom (n : ) :
n.choose 2 * Nat.choose 4 2 = 3 * n * (n - 1)
noncomputable def one_on (P : Prop) :
Equations
Instances For
    noncomputable def oneOn (S : Set ) (x : ) :
    Equations
    Instances For
      noncomputable def oneOn' {X : Type u_1} (S : Set X) (x : X) :
      Equations
      • oneOn' S x = S.indicator (fun (x : X) => 1) x
      Instances For
        theorem one_one_inequality_indicator (x : ) (a : ) :
        a * (Set.Ici a).indicator (fun (x : ) => 1) x x
        theorem one_on_inequality (x : ) (a : ) :
        a * one_on (a x) x
        theorem real_one_on_inequality (x : ) (a : ) (g : 0 x) :
        a * (one_on (a x)) x
        theorem real_one_on_inequality' (x : ) (a : ) (g : 0 x) :
        (Set.Ici a).indicator (fun (x : ) => a) x x