1Math::NumSeq::PisanoPerUisoedrStCeopnst(r3i)buted Perl DMoactuhm:e:nNtuamtSieoqn::PisanoPeriodSteps(3)
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6 Math::NumSeq::PisanoPeriodSteps -- Fibonacci frequency and Leonardo
7 logarithm
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10 use Math::NumSeq::PisanoPeriodSteps;
11 my $seq = Math::NumSeq::PisanoPeriodSteps->new;
12 my ($i, $value) = $seq->next;
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15 This is the number of times the "PisanoPeriod" must be applied before
16 reaching an unchanging value.
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18 0, 4, 3, 2, 3, 1, 2, 2, 1, 2, 3, 1, 3, 2, 3, 1, 2, 1, 2, ...
19 starting i=1
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21 As per Fulton and Morris
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23 "On arithmetical functions related to the Fibonacci numbers", Acta
24 Arithmetica, volume 16, 1969, pages 105-110.
25 <http://matwbn.icm.edu.pl/ksiazki/aa/aa16/aa1621.pdf>
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27 repeatedly applying the PisanoPeriod eventually reaches an m which is
28 unchanging, ie. for which PisanoPeriod(m)==m. For example i=5 goes
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30 PisanoPeriod(5)=20
31 PisanoPeriod(20)=60
32 PisanoPeriod(60)=60
33 PisanoPeriod(120)=120
34 so value=3 applications until to reach unchanging 120
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36 Leonardo Logarithm
37 The unchanging period reached is always of the form
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39 m = 24 * 5^(l-1)
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41 The "l" exponent is the Leonardo logarithm. Option "values_type =>
42 "log"" returns that as the sequence values.
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44 0, 1, 1, 1, 2, 1, 1, 1, 1, 2, 2, 1, 1, 1, 2, 1, 1, 1, 1, 2, 1, ...
45 starting i=1
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47 For example the i=5 above ends at m=120=24*5^1 so l-1=1 is l=2 for the
48 sequence value.
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51 See "FUNCTIONS" in Math::NumSeq for behaviour common to all sequence
52 classes.
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54 "$seq = Math::NumSeq::PisanoPeriodSteps->new ()"
55 "$seq = Math::NumSeq::PisanoPeriodSteps->new (values_type => $str)"
56 Create and return a new sequence object.
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58 Random Access
59 "$value = $seq->ith($i)"
60 Return the count or logarithm of $i.
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63 Math::NumSeq, Math::NumSeq::Fibonacci
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66 <http://user42.tuxfamily.org/math-numseq/index.html>
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69 Copyright 2012, 2013, 2014, 2016, 2019 Kevin Ryde
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71 Math-NumSeq is free software; you can redistribute it and/or modify it
72 under the terms of the GNU General Public License as published by the
73 Free Software Foundation; either version 3, or (at your option) any
74 later version.
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76 Math-NumSeq is distributed in the hope that it will be useful, but
77 WITHOUT ANY WARRANTY; without even the implied warranty of
78 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
79 General Public License for more details.
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81 You should have received a copy of the GNU General Public License along
82 with Math-NumSeq. If not, see <http://www.gnu.org/licenses/>.
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86perl v5.32.0 2020-07-28Math::NumSeq::PisanoPeriodSteps(3)