Math::NumSeq::StarNumbers -- star numbers 6*i*(i-1)+1
use Math::NumSeq::StarNumbers; my $seq = Math::NumSeq::StarNumbers->new; my ($i, $value) = $seq->next;
The sequence of star numbers 1, 13, 37, 73, 121, etc, 6*i*(i-1)+1, also called the centred 12-gonals.
See "FUNCTIONS" in Math::NumSeq for behaviour common to all sequence classes.
$value = $seq->ith($i)
$bool = $seq->pred($value)
Return true if
$valueis of the form 6*i*(i-1)+1 for some i.
$i = $seq->value_to_i_floor($value)
$i = $seq->value_to_i_estimate($value)
Return the i for the star number <= $value.
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/>.