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Q: Geometric name for d20?

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Brian Trosko

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Mar 26, 1995, 6:50:09 PM3/26/95
to
Qbert (qb...@telerama.lm.com) wrote:

: I know the names for all the others, but what's the name for 20 sided
: die? In case you think it's a dodecahedron, that is a d12 (sounded
: like a 20 to me though) If anyone knows, could you Email me asap? I
: need it for a school assignment due tomarrow. Thanks :)
: qbert


Icosahedron, I believe. At least, that's what it said in my 10th grade
geometry text. But that was a long time ago, and they may have changed it.


Brian "It's one of those Euclidian polywhatsits" Trosko

Qbert

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Mar 26, 1995, 11:36:04 AM3/26/95
to

I know the names for all the others, but what's the name for 20 sided
die? In case you think it's a dodecahedron, that is a d12 (sounded
like a 20 to me though) If anyone knows, could you Email me asap? I
need it for a school assignment due tomarrow. Thanks :)
qbert
(qb...@telerama.lm.com)

Dru A Smith

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Mar 26, 1995, 3:26:39 PM3/26/95
to

For all interested:

d4 = Tetrahedron
d6 = Hexahedron (cube)
d8 = Octahedron
d10 = Not a regular polyhedron, not sure if this has a name
d12 = Dodecahedron
d20 = *ICOSAHEDRON*
d30 = Not a regular polyhedron
d100 = Not a regular polyhedron

Dru Smith
----------------------------------------------------------------
"...all life is only a set of pictures in the brain, among which
there is no difference betwixt those born of real things and
those born of inward dreamings, and no cause to value the one
above the other"
-- H.P. Lovecraft, The Silver Key

Menno Deij

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Mar 27, 1995, 8:54:22 AM3/27/95
to qb...@telerama.lm.com
On 26 Mar 1995 11:36:04 -0500,
Qbert <qb...@telerama.lm.com> wrote:

>
>I know the names for all the others, but what's the name for 20 sided
>die? In case you think it's a dodecahedron, that is a d12 (sounded
>like a 20 to me though) If anyone knows, could you Email me asap? I
>need it for a school assignment due tomarrow. Thanks :)
>qbert
>(qb...@telerama.lm.com)
>

In Holland we call the d20 a icosa der, so in US it must be something like
icosahedron.
Hope to help ye out!
Greetings,
Menno.

Christopher Wooff

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Mar 27, 1995, 12:07:47 PM3/27/95
to

I wouldn't call the polyhedra "Euclidean polywhatsits"; maybe the term
you're looking for is "Platonic solids".

Chris Wooff

Jeff S Rogers grdstu

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Mar 27, 1995, 12:17:19 PM3/27/95
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In article <3l4ujh$1...@news.primenet.com>,

Brian Trosko <btr...@primenet.com> wrote:
>Qbert (qb...@telerama.lm.com) wrote:
>
>: I know the names for all the others, but what's the name for 20 sided
>: die? In case you think it's a dodecahedron, that is a d12 (sounded
>: like a 20 to me though) If anyone knows, could you Email me asap? I
>: need it for a school assignment due tomarrow. Thanks :)
>: qbert
>
>
>Icosahedron, I believe. At least, that's what it said in my 10th grade
>geometry text. But that was a long time ago, and they may have changed it.
>
>
Yes, 20 sided polygons are calle "Icosahedrons". The shape is
prevalent among the adenoviruses (which causes a host of diseases
e.g. conjunctivities/Pink eye, rhinitis and sometimes are tumorigenic)
Look up a Virology text and check out EM pictures of Adenoviruses, some
have spikes coming out of their points and look like a Sputnik... :)

Just FYI....

-Jeff

########################################################################
# J.S. Rogers ---> jro...@umassmed.ummed.edu # Bitton's Postulate: #
# University of Massachusetts Medical Center # "If you understand it,#
# Graduate School of Biomedical Sciences # it's obsolete." #
# Worcester, MA 01604 # #
#################################Melekurion abatha!#####################


Monument

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Mar 27, 1995, 7:29:56 PM3/27/95
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Jeff S Rogers grdstu (jro...@umassmed.UMMED.EDU) wrote:
: Yes, 20 sided polygons are calle "Icosahedrons". The shape is
: prevalent among the adenoviruses (which causes a host of diseases
: e.g. conjunctivities/Pink eye, rhinitis and sometimes are tumorigenic)
: Look up a Virology text and check out EM pictures of Adenoviruses, some
: have spikes coming out of their points and look like a Sputnik... :)

ICK! I guess that's the last time I curse a d20... it might jump into
my eye and give me a very nasty spelled disease. ;)

----------------------------------------------------------------------------
| Jeff Goslin - Monument | "Oh Bentson, you are so |
| jggo...@vela.acs.oakland.edu | mercifully free from the |
| jggo...@pollux.acs.oakland.edu | ravages of intellect." |
| http://www.acs.oakland.edu/links/jggoslin | --Evil, The Time Bandits |
----------------------------------------------------------------------------
| "You can always retake a class, but you can never relive a party." |
----------------------------------------------------------------------------

Cody Kosinski

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Mar 28, 1995, 4:06:00 PM3/28/95
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"Menno Deij" <s940...@student.utwente.nl> writes:

It's called the Isosagon. You were close though.. Later.

Aragorn

--
Cody Kosinski co...@ersys.edmonton.ab.ca
Edmonton Remote Systems Serving Edmonton/Northern Alberta since 1982

Vince Hickey

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Mar 28, 1995, 8:52:03 AM3/28/95
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d10 = decahedron

In article <3l4ilv$s...@charm.magnus.acs.ohio-state.edu>,

Dru A Smith

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Mar 28, 1995, 9:30:16 AM3/28/95
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In article <Vince_Hickey-2...@octopus1.nrl.navy.mil>,
Vince Hickey <Vince_...@kingcrab.nrl.navy.mil> wrote:
>
>d10 = decahedron

I was gonna say this, but held my tongue, thinking that only the
Platonic Solids had the <prefix>-hedron names... sheesh, was I wrong!

Anyway, thanks for the reminder :)

Jeff Kesselman

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Mar 29, 1995, 3:00:00 AM3/29/95
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Dodecahedron.

I knew Latin would come in handy someday :)

JK

Jeff Kesselman

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Mar 29, 1995, 3:00:00 AM3/29/95
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In article <3l455k$m...@asia.lm.com>, qb...@telerama.lm.com (Qbert) wrote:

I don't beliebve I just did that, but it escaped before I could cancel.

ICOSAhedron.

So much for my latin. Its late and your reference above stuck in my mind
too well!

:: oops::

JK

Chris Bourne

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Mar 29, 1995, 3:00:00 AM3/29/95
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In article <jeffpk-2708...@192.0.2.1>
jef...@netcom.com "Jeff Kesselman" writes:

> In article <3l455k$m...@asia.lm.com>, qb...@telerama.lm.com (Qbert) wrote:
>

> Dodecahedron.
>
> I knew Latin would come in handy someday :)
>
> JK
>

Except it's from the Greek... :)
--
Chris Bourne

Stephan Baitz

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Mar 29, 1995, 3:00:00 AM3/29/95
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drus...@magnus.acs.ohio-state.edu (Dru A Smith) wrote:
>
> For all interested:
>
> d4 = Tetrahedron
> d6 = Hexahedron (cube)
> d8 = Octahedron
> d10 = Not a regular polyhedron, not sure if this has a name

the d10 is a pentagonal scalenohedron (sp??, can't find it in my dictionary 8-[ )
("pentagonales Skalenoeder" in German)

> d12 = Dodecahedron
> d20 = *ICOSAHEDRON*
> d30 = Not a regular polyhedron

I think this one is called _triacontahedron_

[...]

Stephan Baitz

Roger van Velzen

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Mar 29, 1995, 3:00:00 AM3/29/95
to hod...@prl.philips.co.uk
On Tue, 28 Mar 1995 15:24:41 GMT,
Ben Hodson <hod...@prl.philips.co.uk> wrote:

>Qbert (qb...@telerama.lm.com) wrote:
>
>: I know the names for all the others, but what's the name for 20 sided
>: die? In case you think it's a dodecahedron, that is a d12 (sounded
>: like a 20 to me though) If anyone knows, could you Email me asap? I
>: need it for a school assignment due tomarrow. Thanks :)
>: qbert
>: (qb...@telerama.lm.com)

>On the subject of dice - does anyone actually use a d100 ? As
>far as I'm concerned one may as well paint numbers on a golf
>ball ! Whats wrong with 2d10 ?
>
>Cheers,
>
>Ben Hodson - hod...@prl.philips.co.uk
>
Nope nothing is wrong with 2d10... I use them here all the time.
I do own a die hundred but:
A) It keeps on rolling too LONG (I had to chase it down the stairs once)
B) Although it is not true; It rolls 96-100 more than my 2d10 could ever
roll in a lifetime.... (just from experiences!)
So as I'm concered: 2d10 RULEZ!!!!!

The Double Decahedron-Lover,

*********************
** R. van Velzen **
**Silver Dragonlord**
*********************
EMAIL:R.van...@student.utwente.nl

Gereon Dahmen

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Mar 29, 1995, 3:00:00 AM3/29/95
to

>Chris Wooff
>
'Platonic solids' is the name for all the five symmetric dices:

d4: tetraeder
d6: hexaeder
d8: octaeder
d12: duodekaeder
d20: ikosaeder

G. Dahmen

Ben Hodson

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Mar 28, 1995, 10:24:41 AM3/28/95
to
Qbert (qb...@telerama.lm.com) wrote:

: I know the names for all the others, but what's the name for 20 sided

Most shapes seem to have a connection with the greek numbers :

Octo - octohedron - eight sided
deca - decahedron - ten sided
thodeca - dodecahedron - twelve sided
ecosy - icosahedron - twenty sided

The spelling of the first column (I wont even call it greek :-)
is only aproximatly phonetic !

Dru A Smith

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Mar 28, 1995, 9:08:15 PM3/28/95
to
In article <P5yo3c...@ersys.edmonton.ab.ca>,

Cody Kosinski <co...@ersys.edmonton.ab.ca> wrote:
>"Menno Deij" <s940...@student.utwente.nl> writes:
>
>> On 26 Mar 1995 11:36:04 -0500,
>> Qbert <qb...@telerama.lm.com> wrote:
>>
>> >
>> >I know the names for all the others, but what's the name for 20 sided
>> >die? In case you think it's a dodecahedron, that is a d12 (sounded
>> >like a 20 to me though) If anyone knows, could you Email me asap? I
>> >need it for a school assignment due tomarrow. Thanks :)
>> >qbert
>> >(qb...@telerama.lm.com)
>> >
>> In Holland we call the d20 a icosa der, so in US it must be something like
>> icosahedron.
>> Hope to help ye out!
>> Greetings,
>> Menno.
>>
>
> It's called the Isosagon. You were close though.. Later.

Actually, Icosagon is the name of a 20 sided 2-D polygon. The
Icosahedron is a 20-faced 3-d polyhedron.

Jeff Kesselman

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Mar 30, 1995, 2:27:02 AM3/30/95
to
In article <3l6rd3$e...@tribune.usask.ca>, wo...@snoopy.usask.ca
(Christopher Wooff) wrote:

> I wouldn't call the polyhedra "Euclidean polywhatsits"; maybe the term
> you're looking for is "Platonic solids".
>

Actually, i believe the term is regular solids.

Platonic suggest the platonic forms which are, according to Plato's
philosophy, the absolutely PERFECT forms of which all physical forms are
imperfect shadows.

Given dice manufacturing tolernces, they are unlikely to by platonic forms.

JK

Lawrence R. Mead

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Mar 30, 1995, 3:00:00 AM3/30/95
to
Roger van Velzen (s930...@mail.student.utwente.nl) wrote:
: On Tue, 28 Mar 1995 15:24:41 GMT,
: Ben Hodson <hod...@prl.philips.co.uk> wrote:

: >Qbert (qb...@telerama.lm.com) wrote:
: >
: >: I know the names for all the others, but what's the name for 20 sided
: >: die? In case you think it's a dodecahedron, that is a d12 (sounded

The 20-sided regular solid is the *icosahedron* .

DMGorgon
--

Lawrence R. Mead (lrm...@whale.st.usm.edu) | ESCHEW OBFUSCATION !
Associate Professor of Physics | ESPOUSE ELUCIDATION !


M. Sun

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Mar 30, 1995, 3:00:00 AM3/30/95
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p65...@fs1.mpifr-bonn.mpg.de (Gereon Dahmen) writes:

>In <3l6rd3$e...@tribune.usask.ca> wo...@snoopy.usask.ca (Christopher Wooff) writes:

>>Chris Wooff
>>


>'Platonic solids' is the name for all the five symmetric dices:

>d4: tetraeder
>d6: hexaeder
>d8: octaeder
>d12: duodekaeder
>d20: ikosaeder

>G. Dahmen
>
They are also called the regular solids, since they are made of all
regular-polygon faces, which are in turn all the same.

In a geometry text (English) you will probably find the Anglicized
versions which are:

d4: tetrahedron
d6: hexahedron (cube)
d8: octahedron
d12: dodecahedron
d20: icosahedron

Also, my favorite die of all:

d1: sphere (ball)
;) ;) ;)

Kate the Short

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Mar 30, 1995, 3:00:00 AM3/30/95
to

I know it's s'posed to be "isocahedron," but I've always heard it referred to
as "duodecahedron," (as opposed to "dodecahedron")

--

Aardy R. Devarque
Feudalism: Serf & Turf
Kate the Short's SO
Ram Python View on War: If it moves, kill it. If it doesn't move, pick it
up and kill it.

| -NOT Kate the Short (KEW...@exodus.valpo.edu) at Valparaiso University- |
| -Well-Argued Points are the Spice of Life, and the Sorrow of the Lawyer- |


dk...@cas.org

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Mar 31, 1995, 3:00:00 AM3/31/95
to
In article b...@charm.magnus.acs.ohio-state.edu, drus...@magnus.acs.ohio-state.edu (Dru A Smith) writes:
>In article <Vince_Hickey-2...@octopus1.nrl.navy.mil>,
>Vince Hickey <Vince_...@kingcrab.nrl.navy.mil> wrote:
>>
>>d10 = decahedron
>
> I was gonna say this, but held my tongue, thinking that only the
>Platonic Solids had the <prefix>-hedron names... sheesh, was I wrong!

No, they apply to the Consummate Solids as well :).

As always any opinions I may have written are mine and mine alone.

Dave.


Intrasoft

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Mar 31, 1995, 3:00:00 AM3/31/95
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Stephan Baitz (ba...@immr.tu-clausthal.de) wrote:
: drus...@magnus.acs.ohio-state.edu (Dru A Smith) wrote:
: >
: > For all interested:

: >
: > d4 = Tetrahedron
: > d6 = Hexahedron (cube)
: > d8 = Octahedron
: > d10 = Not a regular polyhedron, not sure if this has a name
: > d12 = Dodecahedron
: > d20 = *ICOSAHEDRON*
: > d30 = Not a regular polyhedron

: I think this one is called _triacontahedron_

Additionally:
d10 = decahedron,
d100 = hecatontahedron (perhaps with no leading 'h')

These come from the greek names for the corresponding numbers.


dk...@cas.org

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Apr 4, 1995, 3:00:00 AM4/4/95
to
In article P5yo3c...@ersys.edmonton.ab.ca, co...@ersys.edmonton.ab.ca (Cody Kosinski) writes:
>"Menno Deij" <s940...@student.utwente.nl> writes:
>
>> On 26 Mar 1995 11:36:04 -0500,
>> Qbert <qb...@telerama.lm.com> wrote:
>>
>> >
>> >I know the names for all the others, but what's the name for 20 sided
>> >die? In case you think it's a dodecahedron, that is a d12 (sounded
>> >like a 20 to me though) If anyone knows, could you Email me asap? I
>> >need it for a school assignment due tomarrow. Thanks :)
>> >qbert
>> >(qb...@telerama.lm.com)
>> >
>> In Holland we call the d20 a icosa der, so in US it must be something like
>> icosahedron.
>> Hope to help ye out!
>> Greetings,
>> Menno.
>>
>
> It's called the Isosagon. You were close though.. Later.

Say what? In the US it's an Icosahedron (sp?), not an Isosagon.

As always any opinions I may have written above are mine and mine alone.

Dave.


Michael Karapcik (AC)

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Apr 4, 1995, 3:00:00 AM4/4/95
to
dk...@cas.org wrote:
: In article P5yo3c...@ersys.edmonton.ab.ca, co...@ersys.edmonton.ab.ca (Cody Kosinski) writes:

: >"Menno Deij" <s940...@student.utwente.nl> writes:
: >> On 26 Mar 1995 11:36:04 -0500,
: >> Qbert <qb...@telerama.lm.com> wrote:
: >> >I know the names for all the others, but what's the name for 20 sided
: >> >die? In case you think it's a dodecahedron, that is a d12 (sounded
: >> >like a 20 to me though) If anyone knows, could you Email me asap? I
: > It's called the Isosagon. You were close though.. Later.
: Say what? In the US it's an Icosahedron (sp?), not an Isosagon.
: Dave.

Hello.

In geometry (in America), X-gon is a two dimentional shape, and
X-hedron is a three dimentional shape, with X being the numeric prefix.

4 sided tetrahedron
6 sided hexahedron or cube
8 sided octohedron
10 sided (irregular) decahedron (technically something like
bi-pyramidal decahedron)
12 sided dodecahedron (pentagonal regular dodecahedron, there
is also a rhomboidal dodecahedron)
20 sided icosahedron

I do not have the names for the 30 and 100 sided dice. The d30
is not a platonic solid because the rhomboidal faces are equilinear but
not equiangular (same with rhomboidal dodecahedron), and the faces of
the d100 are neither.
Mike

Robert Johnson

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Apr 4, 1995, 3:00:00 AM4/4/95
to
Heck! Every Virology student knows this one. They're
icosahedrons.

Robert

P.S. FYI Rhinoviruses (which cause common colds) are icosahedrons.
So it HIV, except that it is also an enveloped virus.


All the thing you never wanted to know......

a92...@zipi.fi.upm.es

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Apr 5, 1995, 3:00:00 AM4/5/95
to
In article <3l455k$m...@asia.lm.com>, qb...@telerama.lm.com (Qbert) writes:
>
> I know the names for all the others, but what's the name for 20 sided
> die? In case you think it's a dodecahedron, that is a d12 (sounded
> like a 20 to me though) If anyone knows, could you Email me asap? I
> need it for a school assignment due tomarrow. Thanks :)
> qbert
> (qb...@telerama.lm.com)

That's an icosaedrum.

ARIAKAS; MASTER OF BITS:


Jan-Olof Flink

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Apr 7, 1995, 3:00:00 AM4/7/95
to

Actually the geometric name of a d20 is Ikosaeder.

/JFK

Timothy J McGaha

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Apr 13, 1995, 3:00:00 AM4/13/95
to
: Actually the geometric name of a d20 is Ikosaeder.

The word you're looking for is "icosahedron".

Tim McGaha
Rocket Scientist for Hire, CHEAP!


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