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#21 ALFRED

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Posted 24 March 2008 - 04:29 PM

Well adding 9 is like incrementing the tens place by 1 and decrementing the ones place by 1

17 + 9 =
26

119 + 9 =
128

etc

so adding a multiple of 9 is like doing that multiple times

adding 27 (9*3) is like incrementing the tens place by 3 and decrementing the ones place by 3
example:
55 + 27 =
82

I'm still trying to see how this relates to this riddle, but I think there's probably a connection

I did sorta find one in the other post:

abc+cba = m9 + 2(cba)

where m9 is any multiple of 9, abc is a number (of any amount of digits, i made it abc arbritrarily) and cba is its inverse


on a different point, what IS inversing?

abc would be a*b*c, so what I mean by abc must be:

100a+10b+c

flipped is:
100c+10b+a

so in a three-digit number, flipping means adding 99c and subtracting 99a

is there some sort of pattern we can get for x amount of digits?

a = a, no change needed, keep a the same

10a+b = 10b+a, you need to add 9b and subtract 9a

100a+10b+c = 100c+10b+a, you need to add 99c and subtract 99a, keep be the same

1000a+100b+10c+d = 1000d+100c+10b+a, you need to add 999d, add 90c, subtract 90b and subtract 999a

10000a+1000b+100c+10d+e = 10000e+1000d+100c+10b+a, you need to add 9999e, add 990d, keep c the same, subtract 990b, subtract 9999a

yeah I see a pattern emerging....


I agree unreality. You're definitely onto something here. I'm going to play with those formulas and see if I can come up with something.
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#22 unreality

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Posted 24 March 2008 - 04:43 PM

I made a word document but now it says I cant upload it, and it has a bunch of superscript and subscript stuff and I dont want to convert to bbcode

Is there any way I can get that file up here, cuz it followed thru with those formulas I just started... it's a Word document
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#23 ALFRED

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Posted 24 March 2008 - 05:11 PM

bona and unreality - I don't know if you've seen this yet but it looks like we've just stumbled upon the tip of the iceberg. This guy has been running computer programs for over a decade to compute the largest iterations of palindromic numbers.

World Records
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#24 rookie1ja

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Posted 24 March 2008 - 05:59 PM

I made a word document but now it says I cant upload it, and it has a bunch of superscript and subscript stuff and I dont want to convert to bbcode

Is there any way I can get that file up here, cuz it followed thru with those formulas I just started... it's a Word document

1. send me the file and I will upload it if it's ok
2. make a picture of it - decrease size - upload it

btw, subscript and superscript works in this forum
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#25 niner

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Posted 24 March 2008 - 06:11 PM

After I read this thread, the only thing that comes to mind is

"Why do Native American Raindances work?"


Spoiler for because

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#26 ALFRED

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Posted 24 March 2008 - 10:15 PM

After I read this thread, the only thing that comes to mind is

"Why do Native American Raindances work?"


Spoiler for because


I hate to say it niner but I'm starting to think that's the correct answer.
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#27 unreality

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Posted 25 March 2008 - 04:15 AM

1. send me the file and I will upload it if it's ok


you mean via email? What email address should I send it to?
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#28 scuttill

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Posted 25 March 2008 - 06:04 AM

bona and unreality - I don't know if you've seen this yet but it looks like we've just stumbled upon the tip of the iceberg. This guy has been running computer programs for over a decade to compute the largest iterations of palindromic numbers.

World Records


I was going to sit down and ponder a proof, but that site really discouraged me. Perhaps it is a good thing. I should probably spend that amount of time on something else. Loved this topic, though! :)
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