Similar to ケーニヒの補題

Axiom of choice

Axiom of countable choice

Kőnig's theorem (set theory)

Axiom of dependent choice

Spanning tree

Tychonoff's theorem

Boolean prime ideal theorem

Proof that 22/7 exceeds π

Proof that π is irrational

Euler's formula

Interesting number paradox

Open mapping theorem (complex analysis)

Rank–nullity theorem

Angle bisector theorem

Carathéodory's theorem (convex hull)

Leibniz formula for determinants

Locally connected space

Coupon collector's problem

Casey's theorem

Primitive Pythagorean triple

Cauchy's mean value theorem

Mean value theorem (divided differences)

Schiffler point

Shannon's source coding theorem

Noisy-channel coding theorem

Jordan's lemma

Sylvester–Gallai theorem