Wedgie/Archived version: Difference between revisions

Wikispaces>genewardsmith
**Imported revision 141665907 - Original comment: **
Wikispaces>genewardsmith
**Imported revision 141666273 - Original comment: **
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<h2>IMPORTED REVISION FROM WIKISPACES</h2>
<h2>IMPORTED REVISION FROM WIKISPACES</h2>
This is an imported revision from Wikispaces. The revision metadata is included below for reference:<br>
This is an imported revision from Wikispaces. The revision metadata is included below for reference:<br>
: This revision was by author [[User:genewardsmith|genewardsmith]] and made on <tt>2010-05-13 03:40:22 UTC</tt>.<br>
: This revision was by author [[User:genewardsmith|genewardsmith]] and made on <tt>2010-05-13 03:44:07 UTC</tt>.<br>
: The original revision id was <tt>141665907</tt>.<br>
: The original revision id was <tt>141666273</tt>.<br>
: The revision comment was: <tt></tt><br>
: The revision comment was: <tt></tt><br>
The revision contents are below, presented both in the original Wikispaces Wikitext format, and in HTML exactly as Wikispaces rendered it.<br>
The revision contents are below, presented both in the original Wikispaces Wikitext format, and in HTML exactly as Wikispaces rendered it.<br>
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f^g = sum_s sgn(s) f(x_s(1), x_s(2)...x_s_n)g(x_s(n+1)...x_s(n+m))
f^g = sum_s sgn(s) f(x_s(1), x_s(2)...x_s_n)g(x_s(n+1)...x_s(n+m))


where the sum is taken over S(n,m), the set of all [[http://en.wikipedia.org/wiki/Permutation|permutations]] of the first n+m integers which are an [[http://en.wikipedia.org/wiki/%28p,q%29_shuffle|(n,m) shuffles]], and sgn(t) is the [[http://en.wikipedia.org/wiki/Parity_of_a_permutation|parity of the permutation]] t, which is +1 is even meaning an even number of transpositions of two numbers will get to t, and -1 if it is odd.
where the sum is taken over S(n,m), the set of all [[http://en.wikipedia.org/wiki/Permutation|permutations]] of the first n+m integers which are an [[http://en.wikipedia.org/wiki/%28p,q%29_shuffle|(n,m) shuffles]], and sgn(t) is the [[http://en.wikipedia.org/wiki/Parity_of_a_permutation|parity of the permutation]] t, which is +1 if t is even meaning an even number of transpositions of two numbers will get to t, and -1 if t is odd.


If f and g are both vals (1-maps) then this becomes especially easy: f^g(u,v) = f(u)g(v) - f(v)g(u).  
If f and g are both vals (1-maps) then this becomes especially easy: f^g(u,v) = f(u)g(v) - f(v)g(u).  
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f^g = sum_s sgn(s) f(x_s(1), x_s(2)...x_s_n)g(x_s(n+1)...x_s(n+m))&lt;br /&gt;
f^g = sum_s sgn(s) f(x_s(1), x_s(2)...x_s_n)g(x_s(n+1)...x_s(n+m))&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
where the sum is taken over S(n,m), the set of all &lt;a class="wiki_link_ext" href="http://en.wikipedia.org/wiki/Permutation" rel="nofollow"&gt;permutations&lt;/a&gt; of the first n+m integers which are an &lt;a class="wiki_link_ext" href="http://en.wikipedia.org/wiki/%28p,q%29_shuffle" rel="nofollow"&gt;(n,m) shuffles&lt;/a&gt;, and sgn(t) is the &lt;a class="wiki_link_ext" href="http://en.wikipedia.org/wiki/Parity_of_a_permutation" rel="nofollow"&gt;parity of the permutation&lt;/a&gt; t, which is +1 is even meaning an even number of transpositions of two numbers will get to t, and -1 if it is odd.&lt;br /&gt;
where the sum is taken over S(n,m), the set of all &lt;a class="wiki_link_ext" href="http://en.wikipedia.org/wiki/Permutation" rel="nofollow"&gt;permutations&lt;/a&gt; of the first n+m integers which are an &lt;a class="wiki_link_ext" href="http://en.wikipedia.org/wiki/%28p,q%29_shuffle" rel="nofollow"&gt;(n,m) shuffles&lt;/a&gt;, and sgn(t) is the &lt;a class="wiki_link_ext" href="http://en.wikipedia.org/wiki/Parity_of_a_permutation" rel="nofollow"&gt;parity of the permutation&lt;/a&gt; t, which is +1 if t is even meaning an even number of transpositions of two numbers will get to t, and -1 if t is odd.&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
If f and g are both vals (1-maps) then this becomes especially easy: f^g(u,v) = f(u)g(v) - f(v)g(u).&lt;/body&gt;&lt;/html&gt;</pre></div>
If f and g are both vals (1-maps) then this becomes especially easy: f^g(u,v) = f(u)g(v) - f(v)g(u).&lt;/body&gt;&lt;/html&gt;</pre></div>