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Benny
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 Has anyone seen this before?   « on: May 7th, 2009, 5:30pm » Quote Modify

I came across quite accidentally this forum where it discusses

http://eqworld.ipmnet.ru/forum/viewtopic.php?f=3&t=128

I'm not familiar with "structural geometry"

Then, on the same site, I found at

http://eqworld.ipmnet.ru/forum/viewtopic.php?f=3&t=143

y = x2 + 16

y' at x=3

the author finds y'= 10 ... it's quite extraordinary!
Okay, this result is bogus. But what about the so-called "structural geometry" at the first link ?
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towr
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 Re: Has anyone seen this before?   « Reply #1 on: May 8th, 2009, 12:12am » Quote Modify

There's probably a reason why all replies in that thread are spam.
It's not clear what he's trying to do, nor are his equations even correct in many cases.
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Noke Lieu
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 Re: Has anyone seen this before?   « Reply #2 on: May 8th, 2009, 1:03am » Quote Modify

It's awesome- it's like a ghost town or something. ) registered users, 1 guest, when I looked.
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Benny
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 Re: Has anyone seen this before?   « Reply #3 on: Jun 29th, 2009, 12:15pm » Quote Modify

The second digit is twice the first, the third is twice the second, etc., with "carries" added in as we go along ...
and then we stop when we find a number starting with 10.

................................2
..............................42
............................842
........................16842
......................136842
......................736842
..................14736842
..................94736842
..............1894736842
............17894736842
..........157894736842
........1157894736842
........3157894736842
......63157894736842
...1263157894736842
...5263157894736842
105263157894736842

Moving the last 2 to the front gives 210526315789473684, manifestly twice 105263157894736842.

This blog also contains Dr. Mutalik's explanation of the phenomenon in terms of arithmetic mod 19.
 « Last Edit: Jun 29th, 2009, 12:22pm by Benny » IP Logged

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towr
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 Re: Has anyone seen this before?   « Reply #4 on: Jun 29th, 2009, 12:34pm » Quote Modify

http://en.wikipedia.org/wiki/Parasitic_number
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Benny
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 Re: Has anyone seen this before?   « Reply #5 on: Jun 29th, 2009, 1:23pm » Quote Modify

on Jun 29th, 2009, 12:34pm, towr wrote:
 http://en.wikipedia.org/wiki/Parasitic_number

Thanks for the link. These numbers are intriguing.
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 Re: Has anyone seen this before?   « Reply #6 on: Jul 14th, 2009, 12:08pm » Quote Modify

Has anyone done this experiment:

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TenaliRaman
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 Re: Has anyone seen this before?   « Reply #7 on: Jul 14th, 2009, 1:25pm » Quote Modify

http://en.wikipedia.org/wiki/Reed%E2%80%93Solomon_error_correction#Data_ storage

-- AI
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Benny
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 Re: Has anyone seen this before?   « Reply #8 on: Sep 18th, 2009, 2:57pm » Quote Modify

Binary Clock

It has a detail PDF document
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Benny
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 Re: Has anyone seen this before?   « Reply #9 on: Sep 28th, 2009, 2:09pm » Quote Modify

Have you seen this book : A = B?

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Benny
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 Re: Has anyone seen this before?   « Reply #10 on: Oct 13th, 2009, 1:55pm » Quote Modify

The Book of Odds is an online statistical encyclopedia.

The Book of Odds is a searchable online database of odds statements, the probabilities of everyday life.
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Benny
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 Re: Has anyone seen this before?   « Reply #11 on: May 12th, 2010, 7:14pm » Quote Modify

I've just read the following: The sum of digits of prime numbers is evenly distributed
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 Re: Has anyone seen this before?   « Reply #12 on: Sep 8th, 2010, 10:44pm » Quote Modify

Furstenberg's Proof of the Infinitude of Primes

Quote:
 Perhaps the strangest is the following topological proof by Fόrstenberg

http://primes.utm.edu/notes/proofs/infinite/topproof.html

What makes this proof so strange?
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rmsgrey
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 Re: Has anyone seen this before?   « Reply #13 on: Sep 9th, 2010, 7:25am » Quote Modify

on Sep 8th, 2010, 10:44pm, BenVitale wrote:
 Furstenberg's Proof of the Infinitude of Primes     http://primes.utm.edu/notes/proofs/infinite/topproof.html   What makes this proof so strange?

If you look at the other proofs listed on that site, they are all couched in the language of arithmetic. They talk about taking a list of distinct primes (or a list of numbers that represent distinct primes), performing arithmetic operations on them, and producing a number that represents a new prime.

The topological proof is, unsurprisingly, couched in the language of topology, so, while it's actually saying pretty much the same thing as the other proofs - that no finite set of primes can cover the integers with their multiples - there will always be some numbers that aren't divisible by any of the primes in the set, it's saying it in an unusual way.

Also, it's a non-constructive existence proof - it doesn't tell you anything about how to find these non-multiples, just that they must exist - the other proofs all tell you where to look for your new prime.
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Benny
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 Re: Has anyone seen this before?   « Reply #14 on: Nov 30th, 2011, 2:42pm » Quote Modify

A regular expression to check for prime numbers

http://www.noulakaz.net/weblog/2007/03/18/a-regular-expression-to-check- for-prime-numbers/

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 Re: Has anyone seen this before?   « Reply #15 on: Nov 30th, 2011, 10:11pm » Quote Modify

It actually checks for non-primes
And it's a bit irregular for a regular expression, since you can't translate it to a finite state machine.
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