Thematics Of Order -- Discussion
Jon Awbrey
jawbrey at att.net
Fri Apr 15 22:12:26 CEST 2005
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TOO. Discussion Note 1
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AK = Antti Karttunen
JA = Jon Awbrey
PC = Peter Cameron
Re: TOO. http://stderr.org/pipermail/inquiry/2005-April/thread.html#2541
In part:
JA: How much of the additive, linear, or total order in the
sequence of natural numbers is "purely multiplicative",
that is, how much of the order can be determined
solely by inspection of primes factorizations?
PC comments:
PC: I think it was Ulam who remarked that there are
rings which are multiplicatively isomorphic to
the integers but additively completely different.
One striking example is the polynomial ring over
the integers mod 3.
AK comments:
AK: Please give us an example, how do you induce/produce permutations of
the Natural numbers this way, or tell us whether there are already
illustrative specimens in the OEIS. (It is then much easier for
my concrete mind to grasp the concept ...)
Antti, Peter,
I'm reporting on some diversions that have diverted me for many years,
and this whole arena is littered with a host of tantalizing analogies
and disappointing disanalogies. Memory is mercifully dim about some
of the avenues and deadends, but I can remember as a kid looking at
what I used to call the "vector logarithm" of a natural number n,
its sequence of exponents <e_i> on the sequence of primes <p_i>
and wondering if there were "structure constants" <a_ijk> that
would make addition into an algebraic operation on the lists
of primes factorization exponents. Much diversion was had.
But for the sake of this excursion I'm really just about to
throw away almost all of the properly algebraic information
and ask a mutated version of the earlier question, to wit:
How much of the additive, linear, or total order in the
sequence of natural numbers is "purely combinatorial",
that is, how much of the order can be determined
solely by inspection of the "riffs" or "rotes"
of natural numbers? Definitions to follow,
but in the meantime:
Cf: http://www.research.att.com/projects/OEIS?Anum=A061396
Cf: http://www.research.att.com/projects/OEIS?Anum=A062504
Cf: http://www.research.att.com/projects/OEIS?Anum=A062537
Cf: http://www.research.att.com/projects/OEIS?Anum=A062860
Cf: http://www.research.att.com/~njas/sequences/a061396a.txt
Jon Awbrey
PS. Because of its cross-disciplinary nature,
this discussion is being cross-posted to
several different lists -- anybody who
doesn't what their comments blogged
please let me know. Thanks, JA.
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inquiry e-lab: http://stderr.org/pipermail/inquiry/
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