PrimeFactors

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primefactors(a, separate(optional))

 

Returns a list value that contains the prime factors of a. The result of this function is normally place

 

$p = primefactors(75) = 3, 5:2                

 

The factors can be accessed individually using references

 

$p[1] = 3

$p[2] = 5:2

 

The notation 5:2 indicates that the factor 5 occurs with a frequency of 2 (5^2). You can access the data value and the frequency separately using the datavalue and freq commands.

 

{datavalue($p[2])} = 5

{freq($p[2])} = 2

 

Adding a non-zero second parameter tells the primefactor command to separate out repeated factors instead of using frequencies.

 

primefactors(75,1) = 3, 5, 5