Most (Historically) "Distinguished" Number(s)?
ZAKIRS
zfseidov at ycariel.yosh.ac.il
Tue Sep 17 17:17:01 CEST 2002
Rick, my humble opinion is it's mainly a problem of nomenclature:
how many "properties" of numbers we know?
Your 1597 (with your 5+ simultaneous properties)
has some other properties as well:
reversed 7951 and three other permutations are all prime:1579, 1759 and
5179,
(in total 5 permutations are prime),
all five (?!):
consist of odd integers only,
sum-of-integers is 22,
factors of which are 2 and 11 - the only even prime and smallest prime
repunit....ad infinity. zak
really there is a quotation USELESS BEAUTY OF PRIMES -
in other words what is important and what isn't - who knows..
-----Original Message-----
From: Rick Shepherd [mailto:R.Shepherd at prodigy.net]
Sent: Tuesday, September 17, 2002 4:13 PM
To: Sequence Fanatics
Subject: Most (Historically) "Distinguished" Number(s)?
Recent messages remind me of some questions I posed to
myself recently:
What positive integer (or, ideally, sequence of numbers for the OEIS)
simultaneously possesses n properties, n maximal, where the
properties have all been considered important enough historically to
receive (well-known) names?
For example, prime Fibonacci numbers share two properties.
There are lots of similar examples with two shared properties
(already in the OEIS), involving, say, different types of
figurate numbers.
Recently I found that...
2,1597,? are prime Fibonacci central polygonal numbers
(three shared properties). 1597 is also odd and lucky (5+
simultaneous properties), etc. (I found no other prime
Fibonacci central polygonal numbers among the first
65000+ Fibonacci numbers.). So, 1597 is a very first
shot at such a distinguished number, but...
How big does n, the number of properties, need to be in order
for the number or sequence to be truly "distinguished" or
remarkable?
Finally, because of the fact that "small" numbers are overworked
(and underpaid), I'm sure that any such distinguished numbers
must be at least of a certain size, whatever that may happen to mean.
Regards,
Rick Shepherd
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