Math::NumSeq::PrimeFactorCount -- how many prime factors
use Math::NumSeq::PrimeFactorCount; my $seq = Math::NumSeq::PrimeFactorCount->new; my ($i, $value) = $seq->next;
The sequence of how many prime factors in i, being 0, 1, 1, 2, 1, 2, etc.
The sequence starts from i=1 and that 1 is taken to have 0 prime factors. Then i=2 and i=3 are themselves primes, so 1 prime factor. Then i=4 is 2*2 which is 2 prime factors.
The multiplicity => "distinct" option can control whether repeats of a prime factors are counted, or only distinct primes. For example with "distinct" i=4=2*2 is just 1 prime factor.
multiplicity => "distinct"
$seq = Math::NumSeq::PrimeFactorCount->new ()
$seq = Math::NumSeq::PrimeFactorCount->new (multiplicity => 'distinct')
Create and return a new sequence object.
$value = $seq->ith($i)
Return the number of prime factors in $i.
$i
$bool = $seq->pred($value)
Return true if $value >= 0, being possible counts of prime factors which can occur in the sequence.
$value >= 0
Math::NumSeq, Math::NumSeq::Primes, Math::NumSeq::LiouvilleFunction, Math::NumSeq::MobiusFunction
http://user42.tuxfamily.org/math-numseq/index.html
Copyright 2010, 2011 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/>.
To install Math::NumSeq, copy and paste the appropriate command in to your terminal.
cpanm
cpanm Math::NumSeq
CPAN shell
perl -MCPAN -e shell install Math::NumSeq
For more information on module installation, please visit the detailed CPAN module installation guide.