Sign
The sign of a number, also called Sgn, is 
for a Negative number (i.e., one with a Minus Sign``
''), 0 for the number Zero, or 
for a Positive number (i.e., one with a Plus Sign ``
'').
- Adem Relations
- Adequate Knot
- Adiabatic Invariant
- Adjacency Matrix
- Adjacency Relation
- Adjacent Fraction
- Adjacent Value
- Adjacent Vertices
- Adjoint Curve
- Adjoint Matrix
- Adjoint Operator
- Adjugate Matrix
- Adjunction
- Adleman-Pomerance-Rumely Primality Test
- Adleman-Rumely Primality Test
- Admissible
- Adéle
- Adéle Group
- Affine Complex Plane
- Affine Connection
- Affine Equation
- Affine Geometry
- Affine Group
- Affine Hull
- Affine Plane