Math::NumSeq::Pell -- Pell numbers


 use Math::NumSeq::Pell;
 my $seq = Math::NumSeq::Pell->new;
 my ($i, $value) = $seq->next;


The Pell numbers

    0, 1, 2, 5, 12, 29, 70, ...

where P(k)=2*P(k-1)+P(k-2), starting from i=0 values P(0)=0 and P(1)=1.


See "FUNCTIONS" in Math::NumSeq for behaviour common to all sequence classes.

$seq = Math::NumSeq::Pell->new ()

Create and return a new sequence object.

($i, $value) = $seq->next()

Return the next index and value in the sequence.

When $value exceeds the range of a Perl unsigned integer the return is a Math::BigInt to preserve precision.

Random Access

$value = $seq->ith($i)

Return the $i'th Pell number.

$bool = $seq->pred($value)

Return true if $value is a Pell number.

$i = $seq->value_to_i_estimate($value)

Return an estimate of the i corresponding to $value.


Math::NumSeq, Math::NumSeq::Fibonacci, Math::NumSeq::LucasNumbers



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 <>.