Residuated mapping: Difference between revisions

From formulasearchengine
Jump to navigation Jump to search
en>Northamerica1000
en>Jochen Burghardt
→‎top: def.d residuated, to complete the motivation; removed "iff" from def.
 
Line 1: Line 1:
[[Image:Impossiball solved.jpg|thumb|The Impossiball in its solved state.]]
[[Image:Impossiball scrambled.jpg|thumb|The Impossiball in a scrambled state.]]
[[Image:Impossiball turned.jpg|thumb|The Impossiball partway through a turn, showing how the pieces lift up.]]


The '''Impossiball''' is a rounded [[icosahedron|icosahedral]] puzzle similar to the [[Rubik's Cube]]. It has a total of 20 movable pieces to rearrange, same as the Rubik's Cube, but all of the Impossiball's pieces are corners, like the [[Pocket Cube]].


== History ==
Bonus:  WP Twin and WP Twin Auto Backup: (link to  )  While not a theme, I think this software is essential if you are maintaining your Wordpress blog or regularly create new blog sites. It is used by around 25% of all new websites, and there are more than 27 thousand plugins currently available. A pinch of tablet centric strategy can get your Word - Press site miles ahead of your competitors, so here are few strategies that will give your Wordpress websites and blogs an edge over your competitors:. s and intelligently including a substantial amount of key words in the title tags, image links, etc. This particular wordpress plugin is essential for not only having the capability where you improve your position, but to enhance your organic searches for your website. <br><br>These websites can be easily customized and can appear in the top rankings of the major search engines. If a newbie missed a certain part of the video then they could always rewind. This plugin is a must have for anyone who is serious about using Word - Press. You can up your site's rank with the search engines by simply taking a bit of time with your site. For a Wordpress website, you don't need a powerful web hosting account to host your site. <br><br>In case you have any concerns concerning where and also the best way to utilize [http://9ja.in/wordpress_dropbox_backup_648767 wordpress backup plugin], you can contact us with our own web page. This gives a clearer picture that online shoppers are familiar with the WP ecommerce system. s cutthroat competition prevailing in the online space won. If Gandhi was empowered with a blogging system, every event in his life would have been minutely documented so that it could be recounted to the future generations. The animation can be quite subtle these as snow falling gently or some twinkling start in the track record which are essentially not distracting but as an alternative gives some viewing enjoyment for the visitor of the internet site. If you have any questions on starting a Word - Press food blog or any blog for that matter, please post them below and I will try to answer them. <br><br>Google Maps Excellent navigation feature with Google Maps and latitude, for letting people who have access to your account Latitude know exactly where you are. And, that is all the opposition events with nationalistic agenda in favor of the individuals of Pakistan marching collectively in the battle in opposition to radicalism. Exacting subjects in reality must be accumulated in head ahead of planning on your high quality theme. The company gains commission from the customers' payment. Digital digital cameras now function gray-scale configurations which allow expert photographers to catch images only in black and white. <br><br>A sitemap is useful for enabling web spiders and also on rare occasions clients, too, to more easily and navigate your website. If you operate a website that's been built on HTML then you might have to witness traffic losses because such a site isn't competent enough in grabbing the attention of potential consumers. The days of spending a lot of time and money to have a website built are long gone. You should stay away from plugins that are full of flaws and bugs. You can check out the statistics of page of views for your web pages using free tools that are available on the internet.
William O. Gustafson applied for a patent for the Impossiball design in 1981 and it was issued in 1984.<ref>[http://www.google.com/patents?id=koIzAAAAEBAJ&dq=US+4,474,376 Impossiball patent]</ref> [[Uwe Mèffert]] eventually bought the rights to some of the patents and continues to sell it in his puzzle shop under the Impossiball moniker.
 
== Description ==
The Impossiball is made in the shape of an [[icosahedron]] that has been rounded out to a sphere, and has 20 pieces, all of them corners. The puzzle has twelve circles located at the vertices of the icosahedron, and opposite circles are the same color. Because of the rounded shape of the puzzle, the pieces move up and down as they are rotated. It is also possible to remove one piece, turning the puzzle into a spherical version of the [[15 puzzle]].
 
The purpose of the puzzle is to scramble the colors, and then restore it to its original state of having one color per circle. This puzzle is equivalent to solving just the corners of a [[Megaminx]]. The original Impossiball had the same colors as the Rubik's Cube: red, orange, yellow, green, blue and white. Meffert currently produces two versions, one with six colors and one with twelve. The six-color version (pictured) uses pink, two shades of orange, yellow, green and blue. All the pieces are still distinguishable, however, because the two pieces with the same three colors are mirror images of each other. The twelve-color version has red, pink, orange, yellow, two shades of green, three shades of blue, purple, brown and white.
 
== Solutions ==
In spite of its daunting appearance and greater number of possible positions, the Impossiball is not much more difficult than the standard 2×2×2 [[Pocket Cube]]. This is because it is not a deep-cut puzzle; it only has pentagonal face layers which are similar in structure to the square face layers of the cube. There are no pieces that do not have a counterpart on the cube. Many of the techniques employed in the solution of the Pocket Cube can also be adapted for the Impossiball.
 
== Number of combinations ==
There are 20!/2 ways to arrange the pieces, since there is no way to create odd permutations without tampering with the puzzle. There are 3<sup>19</sup> ways to orient the pieces, since the orientation of the last depends on that of the preceding ones. Since the Impossiball has no fixed face centers, this result is divided by 60. There are 60 possible positions and orientations of the first corner, but all are equivalent because of the lack of face centers.
 
:<math>\frac{20! \times 3^{19}}{120} \approx 2.36 \times 10^{25}</math>
The entire number is 23 563 902 142 421 896 679 424 000 (roughly 23.6 septillion on the [[long and short scales|short scale]] or 23.6 quadrillion on the long scale).
 
== Records ==
{{Empty section|date=July 2008}}
 
== See also ==
*[[Rubik's Cube]]
*[[Megaminx]]
*[[Dogic]]
*[[Alexander's Star]]
*[[Combination puzzles]]
 
==References==
{{reflist}}
 
== External links ==
*[http://www.mefferts.com/ Meffert's puzzle shop]
*[http://www.jaapsch.net/puzzles/impossi.htm Jaap's Impossiball page] &mdash; contains solutions and other information
 
{{Rubik's Cube}}
 
[[Category:Rubik's Cube permutations]]
[[Category:Combination puzzles]]
[[Category:Mechanical puzzles]]
[[Category:Puzzles]]

Latest revision as of 13:50, 28 June 2014


Bonus: WP Twin and WP Twin Auto Backup: (link to ) While not a theme, I think this software is essential if you are maintaining your Wordpress blog or regularly create new blog sites. It is used by around 25% of all new websites, and there are more than 27 thousand plugins currently available. A pinch of tablet centric strategy can get your Word - Press site miles ahead of your competitors, so here are few strategies that will give your Wordpress websites and blogs an edge over your competitors:. s and intelligently including a substantial amount of key words in the title tags, image links, etc. This particular wordpress plugin is essential for not only having the capability where you improve your position, but to enhance your organic searches for your website.

These websites can be easily customized and can appear in the top rankings of the major search engines. If a newbie missed a certain part of the video then they could always rewind. This plugin is a must have for anyone who is serious about using Word - Press. You can up your site's rank with the search engines by simply taking a bit of time with your site. For a Wordpress website, you don't need a powerful web hosting account to host your site.

In case you have any concerns concerning where and also the best way to utilize wordpress backup plugin, you can contact us with our own web page. This gives a clearer picture that online shoppers are familiar with the WP ecommerce system. s cutthroat competition prevailing in the online space won. If Gandhi was empowered with a blogging system, every event in his life would have been minutely documented so that it could be recounted to the future generations. The animation can be quite subtle these as snow falling gently or some twinkling start in the track record which are essentially not distracting but as an alternative gives some viewing enjoyment for the visitor of the internet site. If you have any questions on starting a Word - Press food blog or any blog for that matter, please post them below and I will try to answer them.

Google Maps Excellent navigation feature with Google Maps and latitude, for letting people who have access to your account Latitude know exactly where you are. And, that is all the opposition events with nationalistic agenda in favor of the individuals of Pakistan marching collectively in the battle in opposition to radicalism. Exacting subjects in reality must be accumulated in head ahead of planning on your high quality theme. The company gains commission from the customers' payment. Digital digital cameras now function gray-scale configurations which allow expert photographers to catch images only in black and white.

A sitemap is useful for enabling web spiders and also on rare occasions clients, too, to more easily and navigate your website. If you operate a website that's been built on HTML then you might have to witness traffic losses because such a site isn't competent enough in grabbing the attention of potential consumers. The days of spending a lot of time and money to have a website built are long gone. You should stay away from plugins that are full of flaws and bugs. You can check out the statistics of page of views for your web pages using free tools that are available on the internet.