<s>
The	O
quadratic	B-Algorithm
Frobenius	I-Algorithm
test	I-Algorithm
(	O
QFT	O
)	O
is	O
a	O
probabilistic	B-General_Concept
primality	B-Algorithm
test	I-Algorithm
to	O
determine	O
whether	O
a	O
number	O
is	O
a	O
probable	B-Algorithm
prime	I-Algorithm
.	O
</s>
<s>
It	O
should	O
not	O
be	O
confused	O
with	O
the	O
more	O
general	O
Frobenius	B-Algorithm
test	I-Algorithm
using	O
a	O
quadratic	O
polynomial	O
–	O
the	O
QFT	O
restricts	O
the	O
polynomials	O
allowed	O
based	O
on	O
the	O
input	O
,	O
and	O
also	O
has	O
other	O
conditions	O
that	O
must	O
be	O
met	O
.	O
</s>
<s>
A	O
composite	O
passing	O
this	O
test	O
is	O
a	O
Frobenius	B-Algorithm
pseudoprime	I-Algorithm
,	O
but	O
the	O
converse	O
is	O
not	O
necessarily	O
true	O
.	O
</s>
<s>
The	O
test	O
was	O
later	O
extended	O
by	O
Damgård	O
and	O
Frandsen	O
to	O
a	O
test	O
called	O
extended	O
quadratic	B-Algorithm
Frobenius	I-Algorithm
test	I-Algorithm
(	O
EQFT	O
)	O
.	O
</s>
<s>
If	O
the	O
QFT	O
does	O
n't	O
stop	O
in	O
steps	O
(	O
1	O
)	O
–	O
( 5	O
)	O
,	O
then	O
is	O
a	O
probable	B-Algorithm
prime	I-Algorithm
.	O
</s>
