1Math::NumSeq::AllPrimeFUascetrorCso(n3t)ributed Perl DocMuamtehn:t:aNtuimoSneq::AllPrimeFactors(3)
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NAME

6       Math::NumSeq::AllPrimeFactors -- prime factors of the integers
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SYNOPSIS

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

14       This is a list of the prime factors of the integers 2, 3, 4, etc
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16           starting i=1
17           2, 3, 2, 2, 5, 2, 3, 7, 2, 2, 2, 3, 3, 2, 5, 11, ...
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19                 \--/     \--/     \-----/  \--/  \--/
20                  4    5   6    7    8       9     10   11
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22   Order
23       The optional "order" parameter (a string) can control the order of the
24       primes within each integer,
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26           "ascending"     the default
27           "descending"
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29       For example "descending" rearranges the values to
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31           # order => "descending"
32           2, 3, 2, 2, 5, 3, 2, 7, 2, 2, 2, 3, 3, 5, 2, 11, ...
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34                 \--/     \--/     \-----/  \--/  \--/
35                  4    5   6    7   8        9     10   11
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37       The first difference is 3,2 for 6 (instead of 2,3).
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39   Multiplicity
40       Option "multiplicity => "distinct"" can give just one copy of each
41       prime factor.
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43           # multiplicity => "distinct"
44           2, 3, 2, 5, 2, 3, 7, 2, 3, 2, 5, 11, ...
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46                       \--/           \--/
47                 4  5   6    7  8  9   10   11
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49   On Values
50       Option "on_values" can give the prime factors of just some integers,
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52           "all"           the default
53           "composites"    the non-primes from 4 onwards
54           "odd"           odd integers 3 onwards
55           "even"          even integers 2 onwards
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57       "odd" is not simply a matter of filtering out 2s from the sequence,
58       since it takes the other primes from the even integers too, such as the
59       3 from 6.
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61           # on_values => "odd"
62           3, 5, 7, 3, 3, 11, 13, 3, 5, 17,
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64                    \--/          \--/
65                     9             15
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FUNCTIONS

68       See "FUNCTIONS" in Math::NumSeq for behaviour common to all sequence
69       classes.
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71       "$seq = Math::NumSeq::AllPrimeFactors->new ()"
72       "$seq = Math::NumSeq::AllPrimeFactors->new (order => $str, multiplicity
73       => $str, on_values => $str)"
74           Create and return a new sequence object.
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76       "$bool = $seq->pred($value)"
77           Return true if $value occurs in the sequence.  This simply means
78           $value a prime, or for "on_values=>'odd'" an odd prime.
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SEE ALSO

81       Math::NumSeq, Math::NumSeq::PrimeFactorCount, Math::NumSeq::AllDigits
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HOME PAGE

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

87       Copyright 2012, 2013, 2014, 2016 Kevin Ryde
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89       Math-NumSeq is free software; you can redistribute it and/or modify it
90       under the terms of the GNU General Public License as published by the
91       Free Software Foundation; either version 3, or (at your option) any
92       later version.
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94       Math-NumSeq is distributed in the hope that it will be useful, but
95       WITHOUT ANY WARRANTY; without even the implied warranty of
96       MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
97       General Public License for more details.
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99       You should have received a copy of the GNU General Public License along
100       with Math-NumSeq.  If not, see <http://www.gnu.org/licenses/>.
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104perl v5.30.1                      2020-01-30  Math::NumSeq::AllPrimeFactors(3)
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