ABS algorithm

 AIMMS

 AMPL

ANALYZE

 Abstract program

 Active constraint

Active set method

 Activity analysis

 Acyclic

Adjacency matrix

 Adjacent basis

 Adjoint

Admissible

 Advanced basis

 Affine combination

Affine function

 Affine hull

 Affine independence

Affine scaling

 Affine set

 Aggregation

Algorithm

 Alldifferent constraint

 Almost complementary

Alternative systems

 Analytic center

 Ant colony optimization

Anticycling rule

 Approximation algorithm

 Arborescent sets

Arc consistency

 Argmax

 Argmin

Artificial variable

 Assembly line balancing problem

 Assignment polytope

Assignment problem

 Asymptotic LP

 Asymptotic stability

Atleast constraint

 Atmost1 constraint

 Atmost constraint

Auction algorithm

 Augmented Lagrangian

 Augmenting path

Automatic differentiation

