Symbols relating to logic and proofs

The following symbols may be used anywhere in text∶
Description
Symbol
Grafstate code
AND
\^
OR
\v
NOT
¬
\!
XOR
(+)
NOR
\!v
NAND
\!^
Logical only if
->
Logical if
<-
Logical if and only if
<->
Only if
implies
=>
If
is implied by
<=
If and only if
<=>
Equivalent
==
Not equivalent
!==
Existential quantifier
there exists
\E
There does not exist
¬∃
\!E
Uniqueness quantifier
there exists exactly one
∃!
\E!
Universal quantifier
for all
\A
Not for all
¬∀
\!A
Therefore
\so
Because
\bc}
Entails (syntax)
\GSSYM derives ;
|-
Does not entail
\GSSYM notderives ;
!|-
End of proof

[]
\qed