Math::N...eFactors(3)

💖 Math::NumSeq::AllPrimeFactors 💖

okay bestie so this is a page from the User Contributed Perl Documentation for the module Math::NumSeq::AllPrimeFactors, and no it's not as scary as the name looks, I promise. it's literally just prime factors of the integers, one after another, like a lil parade. slay. ✨

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🌸 NAME 🌸

Math::NumSeq::AllPrimeFactors — prime factors of the integers, periodt. 💅

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✨ SYNOPSIS ✨

use Math::NumSeq::AllPrimeFactors;
my $seq = Math::NumSeq::AllPrimeFactors->new;
my ($i, $value) = $seq->next;

that's it. that's the whole vibe. 🦋

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🎀 DESCRIPTION 🎀

so what this gives you is a list of the prime factors of the integers 2, 3, 4, etc. all of them. every single factor. no gatekeeping. 👑

    starting i=1
    2, 3, 2, 2, 5, 2, 3, 7, 2, 2, 2, 3, 3, 2, 5, 11, ...

          \--/     \--/     \-----/  \--/  \--/
           4    5   6    7    8       9     10   11

see how it lines up? 4 gives you 2, 2, 6 gives you 2, 3, 8 gives you 2, 2, 2, 12 would keep going, etc etc. iconic behaviour honestly. 🌈

💫 Order 💫

there's an optional order parameter (a string, bestie, a string) that controls the order of the primes within each integer. your choices are:

• "ascending" — the default, chill, normal, we love her
• "descending"

for example, "descending" rearranges the values to:

    # order => "descending"
    2, 3, 2, 2, 5, 3, 2, 7, 2, 2, 2, 3, 3, 5, 2, 11, ...

          \--/     \--/     \-----/  \--/  \--/
           4    5   6    7    8        9     10   11

the first difference shows up as 3, 2 for 6 (instead of 2, 3). yes she flipped it. main character energy. 💅

🧚 Multiplicity 🧚

option multiplicity => "distinct" can give just one copy of each prime factor — like, no repeats, we're keeping it minimal:

    # multiplicity => "distinct"
    2, 3, 2, 5, 2, 3, 7, 2, 3, 2, 5, 11, ...

                \--/           \--/
          4  5   6    7  8  9   10   11

see, 8 used to be three 2s and now she's just one lil 2. so demure. 🎀

🌸 On Values 🌸

option on_values can give the prime factors of just some integers, if you're feeling selective:

• "all" — the default, everybody's invited
• "composites" — the non-primes from 4 onwards
• "odd" — odd integers 3 onwards
• "even" — even integers 2 onwards

real talk: "odd" is not simply a matter of filtering out 2s from the sequence. no ma'am. because it takes the other primes from the even integers too, such as the 3 from 6. iykyk. 😭

    # on_values => "odd"
    3, 5, 7, 3, 3, 11, 13, 3, 5, 17,

             \--/          \--/
              9             15

lowkey a trap if you assume things, fr fr. 🙈

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🔥 FUNCTIONS 🔥

first off: go read "FUNCTIONS" in Math::NumSeq for the behaviour that's common to all sequence classes. that's the shared lore. 📚

• $seq = Math::NumSeq::AllPrimeFactors->new ()
• $seq = Math::NumSeq::AllPrimeFactors->new (order => $str, multiplicity => $str, on_values => $str)

— Create and return a new sequence object. fresh out the box, ready to go. ✨

• $bool = $seq->pred($value)

— Return true if $value occurs in the sequence. and what does that mean, bestie? it simply means $value is a prime, or for "on_values=>'odd'" an odd prime. that's it, that's the whole test. 💯

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🦋 SEE ALSO 🦋

• Math::NumSeq
• Math::NumSeq::PrimeFactorCount
• Math::NumSeq::AllDigits

the whole friend group, go say hi. 🫶

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⭐ HOME PAGE ⭐

<http://user42.tuxfamily.org/math-numseq/index.html>

(the link is right there, go click it, it's giving official.) 💜

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👑 LICENSE 👑

Copyright 2012, 2013, 2014, 2016, 2019, 2020 Kevin Ryde

Math-NumSeq is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3, or (at your option) any later version.

Math-NumSeq is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with Math-NumSeq. If not, see <http://www.gnu.org/licenses/>.

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okay and that's the whole page, bestie!! 🎉 this one's from perl v5.42.0, dated 2025-07-25 — so yes, she's recent, she's maintained, she's that girl. go factor some primes. mwah. 💖🌸💅