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, 2012 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/>.