Symbols used for computation and computer science

See the glossary of notation related to computation .
Also see the other math symbols in Grafstate .

The following symbols can be used anywhere in text∶
Description
Symbol
Grafstate code
Concatenation (of strings)
·
\.
Concatenation (of languages)
∘
\@
Kleene closure
*
*
Transition function
δ
\d
Input alphabet
Σ
\S
Stack ( PDAs ) ∕ tape ( TMs ) alphabet
Τ
\T
Strings in ascending short lexicographical order
≪
<<
Strings in descending short lexicographical order
≫
>>
Blank symbol (TMs)
␣
\_
Empty string
ε
\e
Empty language
∅
{}
\0
{}
Rule expansion
⟶
->
Derivation step
⟹
=>
Derives (a string)
\GSSYM derives ;
|-
Does not derive
\GSSYM notderives ;
!|-
Equivalent (computational structures)
≅
~=
Not equivalent
≇
!~=
Many-to-one reducible (mapping reducible)
≤m
\mred
Big-O
𝒪
\O
little-o
o
o
Big-Omega
Ω
\Omega
little-omega
ω
\omega
Big-Theta
Θ
\Theta
little-theta
θ
θ
\th
\theta