RMU – Computer and Information Systems
Symbols, Signs, Operators


Symbol 
negation 
not 
Ø ~ 
conjunction 
and 
Ù & 
disjunction 
or 
Ú 
exclusive or 
xor 
Å BA: Å 
nand 
nand 
h 
nor 
nor 
¯ 
conditional, material implication, implies 
If… then… 
® ÉÞ 
biconditional, material equivalence 
…if and only if… 
≡ «Û 
identity 

= 
nonidentity 

¹ 
universal quantifier 
for all 
" 
existential quantifier 
for some, for at least one… 
$ 
subset; 

Í Ê 
proper subset A is a proper subset of B 

Ì É 
membership 
is a member of 
Î 
nonmembership 
is not a member of 
Ï 
union 
member of either set or both 
È 
intersection 
member of both sets 
Ç 
Cartesian product or 
(ordered
pairs, tuples) 
´ (crossjoin) 
Join Symbols 
Join (on =) Join (on θ) Where = Where θ Join (+) 
⨝ (join) 
set difference, minus, except 
member of
1st set but not the 2nd 
 or / 
symmetric set difference 
(A Å B) ≡ 
Å Δ 
Set (delimiters) 
set: 
{ } 
Sequence (delimiters) 
sequence: 
⟨ ⟩ 
String (delimiters) 
string: 
" " 
Multiset/Bag (delimiters) 
multiset/bag: 
⟦ ⟧ 
the set of integers 
doublestruck
Z 
Z ℤ 
the set of nonnegative integers; natural numbers; ℕ
⊂ ℤ 
doublestruck
N 
N ℕ 
the set of positive integers 

Z^{+} 
the set of real numbers; 
doublestruck
R 
ℝ 
set replacement 
fat dot 
· 
power set; the set of all subsets (of A) 
doublestruck
P 
P ℙ 
maplet 
maps to 
↦ 
cardinality (of a set X) 

X or #X 
complement (of A), 

_ 
relation 
⟷ 

domain (of
function or relation) 
domain of 
dom 
range (of
function or relation) 
range of 
ran 
injection 
dom = S; ran Ì
T 
⤔ or ↣ 
surjection 
dom = S; ran = T 
⤀ or ↠ 
bijection 
dom = S; ran = T 
⤚↠ 
partial function 
dom Ì S 
⇸ 
total function 
dom = S 
→ 
relational composition 

⨾ 
relational inverse of R 

R^{~} 
Fonts to use for less common symbols (Windows 7): Symbol, Cambria Math, Zed(Z)
References
[DEA1997] Neville Dean, The Essence of Discrete Mathematics (Pearson Prentice Hall, 1997).
[BAR1993:4] Jon Barwise and John Etchmendy, Tarski’s World (CLSI, 1993)
Updated: 20110213