NAME

Math::NumSeq::DigitProduct -- product of digits

SYNOPSIS

use Math::NumSeq::DigitProduct;
my $seq = Math::NumSeq::DigitProduct->new (radix => 10);
my ($i, $value) = $seq->next;

DESCRIPTION

The products of the digits of i, for example at i=456 the value is 4*5*6=120. i=0 is treated as a single digit 0, so it's product is 0.

For binary (radix => 2) the digits are all just 0 or 1 which means the product is 1 for numbers 0b1, 0b11, 0b111, etc, 2**k-1, or 0 otherwise.

FUNCTIONS

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

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

$seq = Math::NumSeq::DigitProduct->new (radix => $r)

Create and return a new sequence object. The default radix is 10, ie. decimal, or a radix parameter can be given.

Random Access

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

Return the product of the digits of $i.

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

Return true if $value is the product of some set of digits. This means its factors (prime factors) are all less than the radix, since nothing bigger can occur.

SEE ALSO

Math::NumSeq, Math::NumSeq::DigitLength, Math::NumSeq::DigitSum

HOME PAGE

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

LICENSE

Copyright 2011, 2012, 2013, 2014, 2016, 2019 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/>.