Similar to ド・ブラウン・インデックス

Ackermann function

Atiyah–Singer index theorem

Sieve of Atkin

Apéry's constant

Apéry's theorem

Abel–Plana formula

Apollonian gasket

Apollonius point

Erlang distribution

Archimedes's cattle problem

Archimedean property

Twin circles

Algorithm

Artin L-function

Artin–Hasse exponential

Wedderburn–Artin theorem

Artinian module

Artinian ring

Artin–Schreier theory

Artin reciprocity

Artin–Rees lemma

Albanese variety

Alexander polynomial

List of things named after Alexander Grothendieck

Alexandrov theorem