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1 x 8 + 1 = 9
12 x 8 + 2 = 98
123 x 8 + 3 = 987
1234 x 8 + 4 = 9876
12345 x 8 + 5 = 98765
123456 x 8 + 6 = 987654
1234567 x 8 + 7 = 9876543
12345678 x 8 + 8 = 98765432
123456789 x 8 + 9 = 987654321
1 x 9 + 2 = 11
12 x 9 + 3 = 111
123 x 9 + 4 = 1111
1234 x 9 + 5 = 11111
12345 x 9 + 6 = 111111
123456 x 9 + 7 = 1111111
1234567 x 9 + 8 = 11111111
12345678 x 9 + 9 = 111111111
123456789 x 9 +10= 1111111111
9 x 9 + 7 = 88
98 x 9 + 6 = 888
987 x 9 + 5 = 8888
9876 x 9 + 4 = 88888
98765 x 9 + 3 = 888888
987654 x 9 + 2 = 8888888
9876543 x 9 + 1 = 88888888
98765432 x 9 + 0 = 888888888
And finally, take a look at this symmetry:
1 x 1 = 1
11 x 11 = 121
111 x 111 = 12321
1111 x 1111 = 1234321
11111 x 11111 = 123454321
111111 x 111111 = 12345654321
1111111 x 1111111 = 1234567654321
11111111 x 11111111 = 123456787654321
111111111 x 111111111 = 12345678987654321
Bombing for Peace is like F***ing For Virginity"
My Articles
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That's interesting... I'm just wondering if I can apply it to anything useful. Probably not, but still a fun exercise.
(Nice sig, BTW).
- S
50 cups of coffee and you know it's on!
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Steve Echols wrote: (Nice sig, BTW).
Thanks  That was from a T-Shirt.
Bombing for Peace is like F***ing For Virginity"
My Articles
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The version I know is "fighting" but I guess "bombing" is more relative nowadays.
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a(n) = (n + a(n - 1)*10^L(n)/(1 + 10^(n*L(n - 1) - (10^L(n - 1) - 1)/9)))*(1 + 10^((n + 1)*L(n) - (10^L(n) - 1)/9))
where L(n) = floor[log10(10n)]
11, 1212, 123123, 12341234, 1234512345, 123456123456, 12345671234567, 1234567812345678, 123456789123456789, 1234567891012345678910, 12345678910111234567891011, 123456789101112123456789101112, ...
Ryan "Punctuality is only a virtue for those who aren't smart enough to think of good excuses for being late" John Nichol "Point Of Impact"
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Interesting. Does it carry over into number systems with bases different than 10?
The evolution of the human genome is too important to be left to chance.
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I'm almost done reading Hilbert's Tenth Problem, by Yuri V. Matiyasevich © 1996. This book is way advanced for me, but there are some interesting bits that can be found here[^].
"People who want to share their religious views with you almost never want you to share yours with them." - Anonymous
Web - Blog - RSS - Math - LinkedIn
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Well, it's not long ago, I thought about drawing a twenty sided dice (Ikosaeder on German, I don't find the English expression) with OpenGL on my own. It's easy to draw a four, six or ten sided dice, I know the formulas behind them.
But what about a twenty sided one? Of course I could sit down and figure it out on my own, but perhaps anybody knows a good source on internet where to find formulas for such geometric objects?
Regards,
Ingo
------------------------------
PROST Roleplaying Game
War doesn't determine who's right. War determines who's left.
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ihoecken wrote: Well, it's not long ago, I thought about drawing a twenty sided dice (Ikosaeder on German, I don't find the English expression) with OpenGL on my own.
I'm pretty sure you'r looking for a Icosahedron, which is a 20-sided sphere, not dice.
Anyway, this example is in delphi, but the OGL commands should be easy enough to understand...
http://www.sulaco.co.za/drawing_icosahedron_tutorial.htm[^]
Jeremy Falcon
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Jeremy Falcon wrote: I'm pretty sure you'r looking for a Icosahedron
Right.
Jeremy Falcon wrote: which is a 20-sided sphere, not dice
Well it's called dice, too: Non-cubical dice [^] but it doesn't matter, thank you for that source.
Regards,
Ingo
------------------------------
PROST Roleplaying Game
War doesn't determine who's right. War determines who's left.
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ihoecken wrote: Well it's called dice, too: Non-cubical dice [^]
 Well, I'll be. I'm learning myself, so work with me here.
ihoecken wrote: thank you for that source.
No problem.
Jeremy Falcon
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Ok, I just read that link. I think they are referring to it as a die (dice) because of it's use, not it's shape - which is still a sphere.
The distinction is important because searching for the right term will help you find the results you want - which is what I did for that link.
Jeremy Falcon
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Jeremy Falcon wrote: Ok, I just read that link. I think they are referring to it as a die (dice) because of it's use, not it's shape - which is still a sphere.
Sorry, you might be right. That's a translation problem. In German a sphere just mean a "ball" without edges, for us it's a "Polyeder" or dice (Würfel). So I learned something about English language, too. 
Regards,
Ingo
------------------------------
PROST Roleplaying Game
War doesn't determine who's right. War determines who's left.
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ihoecken wrote: In German a sphere just mean a "ball" without edges
At least in the 3D world it's still considered a sphere/ball, just with fewer polygons. Of course, I'm still new to OGL myself.
Anyway, if searching for "dice" doesn't work, you at least have another option now.
Jeremy Falcon
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ihoecken wrote: In German a sphere just mean a "ball" without edges, for us it's a "Polyeder" or dice (Würfel).
Well, when I think of "sphere", I think of "ball". Maybe the English word you want is "polyhedron", which is the three-dimensional analogue of a polygon.
http://en.wikipedia.org/wiki/Polyhedron[^]
http://mathworld.wolfram.com/Polyhedron.html[^]
-- modified at 12:44 Thursday 27th July, 2006 - Clickety police on myself!
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ricecake wrote: Well, when I think of "sphere", I think of "ball". Maybe the English word you want is "polyhedron", which is the three-dimensional analogue of a polygon.
It wasn't me who said that a polyhedron is a sphere, I wondered myself.
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PROST Roleplaying Game
War doesn't determine who's right. War determines who's left.
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Right, actually I was agreeing with you, but also giving you another search term you can use (I didn't see "polyhedron" mentioned explicitly).
--
Marcus Kwok
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ricecake wrote: Maybe the English word you want is "polyhedron", which is the three-dimensional analogue of a polygon.
Thanks for the term.
Jeremy Falcon
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Computer scientists (beginners) hunt an elephant therby starting following algorithm:
1. goto africa
2. start at cape of good hope
3. go through africa from south to north and bidirectional from east to west
4. for every loop:
5. hunt every animal you can find
6. compare every animal with the animal given as elephant
7. stop on match
Mathematicians (beginners) hunt elephants by terminating every animal that is not an elephant and then hunting one exemple of the remaining set.
Mathematicians (advanced) try to proof the excistence of elephants before they start with the beginners method as an inferior exercise.
Mathematic professors proof the existence of one elephant at minimum and then give their students the exercise to hunt a real elephant.
Statisticians shot one time in front of the elephant, one time behind the elephant, so that the elephant is statistically dead.
Economists don't hunt any elephants, but they are convinced that elephants deliver themselves up, if enough money is paid to them.
Java-Programmers make a type cast from a midge. (Same for C# Programmers) 
Regards,
Ingo
------------------------------
PROST Roleplaying Game
War doesn't determine who's right. War determines who's left.
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ihoecken wrote: 1. goto africa
maybe mathematicians finally use VB...
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toxcct wrote: maybe mathematicians finally use VB...
The best and fasted programming language ever? Who knows! 
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PROST Roleplaying Game
War doesn't determine who's right. War determines who's left.
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ihoecken wrote: The best and fasted programming language ever?
ok, i give you a chance : i'm not there, and i didn't hear what you've just said 
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I just encountered a goto statement in some c++ microsoft code (olevar.cpp) today. Either goto is da sh*t, or someone got lazy.
- S
50 cups of coffee and you know it's on!
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might be a trainee who wrote this file... 
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