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.
$seq = Math::NumSeq::StarNumbers->new ()
Create and return a new sequence object.
$value = $seq->ith($i)
Return 6*$i*($i-1)+1
.
$bool = $seq->pred($value)
Return true if $value
is 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.
Math::NumSeq, Math::NumSeq::Polygonal
http://user42.tuxfamily.org/math-numseq/index.html
Copyright 2010, 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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