Math::NumSeq::DigitProduct -- product of digits
use Math::NumSeq::DigitProduct; my $seq = Math::NumSeq::DigitProduct->new (radix => 10); my ($i, $value) = $seq->next;
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.
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.
$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.
Math::NumSeq, Math::NumSeq::DigitLength, Math::NumSeq::DigitSum
http://user42.tuxfamily.org/math-numseq/index.html
Copyright 2011, 2012, 2013, 2014 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.
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