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THIS IS DOCUMENTATION FOR AN OBSOLETE PRODUCT.
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Mathematics and Algorithms
>
Mathematical Functions
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Number Theoretic Functions
>
FactorInteger
>
BUILT-IN MATHEMATICA SYMBOL
Some Mathematical Functions
The Limits of Mathematica
Integer and Number Theoretic Functions
Tutorials »
|
PrimeNu
PrimeOmega
IntegerExponent
Prime
PrimeQ
PrimePowerQ
SquareFreeQ
Divisors
See Also »
|
Algebraic Number Theory
Cryptographic Number Theory
Integer Functions
Mathematical Functions
Number Theoretic Functions
Number Theory
Prime Numbers
New in 6.0: Number Theory & Integer Functions
More About »
FactorInteger
FactorInteger
[
n
]
gives a list of the prime factors of the integer
n
, together with their exponents.
FactorInteger
does partial factorization, pulling out at most
k
distinct factors.
MORE INFORMATION
For negative numbers, the unit
is included in the list of factors.
FactorInteger
also works on rational numbers. The prime factors of the denominator are given with negative exponents.
»
The last element in the list
FactorInteger
gives what is left after the partial factorization.
FactorInteger
[
n
,
GaussianIntegers
->
True
]
factors over Gaussian integers.
»
FactorInteger
automatically works over the Gaussian integers.
When necessary, a unit of the form
,
{
I
, 1}
, or
{-
I
, 1}
is included in the list of factors.
FactorInteger
[
n
,
Automatic
]
pulls out only factors that are easy to find.
FactorInteger
uses
PrimeQ
to determine whether factors are prime.
EXAMPLES
CLOSE ALL
Basic Examples
(2)
Find prime factors and their exponents:
Find prime factors and their exponents:
In[1]:=
Out[1]=
In[1]:=
Out[1]=
Scope
(2)
FactorInteger
threads itself element-wise over lists:
FactorInteger
works with rational numbers:
Generalizations & Extensions
(1)
Factor over Gaussian integers:
Applications
(7)
Find factorizations of numbers of the form
:
Display as an explicit product of factors:
Find primes that appear in prime factorization of
only to the first power:
Find all natural numbers up to 100 that are primes or prime powers:
The number of distinct factors of successive numbers:
The highest power of a prime in numbers up to 100:
The number of factors with Gaussian integers allowed:
Possible Issues
(1)
Timings can increase rapidly and unpredictably with the size of the input:
SEE ALSO
PrimeNu
PrimeOmega
IntegerExponent
Prime
PrimeQ
PrimePowerQ
SquareFreeQ
Divisors
TUTORIALS
Some Mathematical Functions
The Limits of
Mathematica
Integer and Number Theoretic Functions
MORE ABOUT
Algebraic Number Theory
Cryptographic Number Theory
Integer Functions
Mathematical Functions
Number Theoretic Functions
Number Theory
Prime Numbers
New in 6.0: Number Theory & Integer Functions
RELATED LINKS
Implementation notes: Numerical and Related Functions
MathWorld
The Wolfram Functions Site
NKS|Online
(
A New Kind of Science
)
New in 1 | Last modified in 6