Similar to ドロー＝ファルニー線定理

Askey scheme

Arzelà–Ascoli theorem

Hadamard matrix

Hadamard transform

Ackermann function

Atiyah–Singer index theorem

Sieve of Atkin

Apéry's constant

Apéry's theorem

Abel–Plana formula

Apollonius point

Apollonian gasket

Archimedes's cattle problem

Twin circles

Algorithm

Artin L-function

Artin–Hasse exponential

Wedderburn–Artin theorem

Artinian module

Artinian ring

Artin–Schreier theory

Varignon's theorem

Euler line

Euler's theorem in geometry

Cavalieri's principle

Carnot's theorem (inradius, circumradius)

Carnot's theorem (perpendiculars)