NAME
Math::NumSeq::Tetrahedral -- tetrahedral numbers i*(i+1)*(i+2)/6
SYNOPSIS
use Math::NumSeq::Tetrahedral;
my $seq = Math::NumSeq::Tetrahedral->new;
my ($i, $value) = $seq->next;
DESCRIPTION
The tetrahedral numbers, 0, 1, 4, 10, 20, 35, 56, etc, i*(i+1)*(i+2)/6.
FUNCTIONS
See "FUNCTIONS" in Math::NumSeq for the behaviour common to all path classes.
$seq = Math::NumSeq::Tetrahedral->new (key=>value,...)
-
Create and return a new sequence object.
$value = $seq->ith($i)
-
Return
$i*($i+1)*($i+2)/6
. $bool = $seq->pred($value)
-
Return true if
$value
has the form i*(i+1)*(i+2)/6 for some positive integer i.
SEE ALSO
Math::NumSeq, Math::NumSeq::Cubes
HOME PAGE
http://user42.tuxfamily.org/math-numseq/index.html
LICENSE
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/>.