NAME

Math::NumSeq::DivisorCount -- how many divisors

SYNOPSIS

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

DESCRIPTION

The number of divisors of i,

1, 2, 2, 3, 2, 4, 2, 4, 3, 4, 2, 6, 2, 4, 4, 5, 2, 6, 2, ...
starting i=1

i=1 is divisible only by 1 so value=1. Then i=2 is divisible by 1 and 2 so value=2. Or for example i=6 is divisible by 4 numbers 1,2,3,6 so value=4.

FUNCTIONS

See "FUNCTIONS" in Math::NumSeq for behaviour common to all sequence classes.

$seq = Math::NumSeq::DivisorCount->new ()

Create and return a new sequence object.

Random Access

$value = $seq->ith($i)

Return the number of prime factors in $i.

This calculation requires factorizing $i and in the current code after small factors a hard limit of 2**32 is enforced in the interests of not going into a near-infinite loop.

$bool = $seq->pred($value)

Return true if $value occurs as a divisor count, which simply means $value >= 1.

SEE ALSO

Math::NumSeq, Math::NumSeq::PrimeFactorCount

Math::Factor::XS

HOME PAGE

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

LICENSE

Copyright 2011, 2012, 2013, 2014, 2016, 2017, 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/>.