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		<id>https://en.formulasearchengine.com/w/index.php?title=Collision_resistance&amp;diff=11419</id>
		<title>Collision resistance</title>
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		<updated>2013-09-05T22:49:33Z</updated>

		<summary type="html">&lt;p&gt;2.233.21.81: The whole expression &amp;quot;birthday paradox&amp;quot; should be quoted (only &amp;quot;birthday&amp;quot; makes little sense...)&lt;/p&gt;
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&lt;div&gt;The &#039;&#039;&#039;Kaup–Kupershmidt equation&#039;&#039;&#039; (named after David J. Kaup and Boris Abram Kupershmidt) is the [[nonlinear]] fifth-order [[partial differential equation]]&lt;br /&gt;
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:&amp;lt;math&amp;gt;u_t = u_{xxxxx}+10u_{xxx}u+25u_{xx}u_x+20u^2u_x = \frac16 (6u_{xxxx}+60uu_{xx}+45u_x^2+40u^3)_x. &amp;lt;/math&amp;gt;&lt;br /&gt;
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It is the first equation in a hierarchy of [[integrable system|integrable equations]] with [[Lax pair|Lax operator]]&lt;br /&gt;
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:&amp;lt;math&amp;gt; \partial_x^3 + 2u\partial_x + u_x, &amp;lt;/math&amp;gt; .&lt;br /&gt;
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Ii has properties similar (but not identical) to those of the better-known [[Korteweg–de Vries equation|KdV hierarchy]] in which the Lax operator has order 2.&lt;br /&gt;
{{Gallery&lt;br /&gt;
|width=250&lt;br /&gt;
|height=200&lt;br /&gt;
|align=center&lt;br /&gt;
|File:Kaup Kupershmidt JacobiSN method animation2.gif|Kaup Kupershmidt JacobiSN method bell solition animation2&lt;br /&gt;
|File:Kaup Kupershmidt JacobiSN method animation3.gif|Kaup Kupershmidt JacobiSN method bell soliton animation3&lt;br /&gt;
|File:Kaup Kupershmidt JacobiSN method animation4.gif|Kaup Kupershmidt JacobiSN method bell soloton  animation4&lt;br /&gt;
|File:Kaup Kupershmidt csch method animation2.gif|Kaup Kupershmidt csch method animation2&lt;br /&gt;
|File:Kaup Kupershmidt csch method animation3.gif|Kaup Kupershmidt csch method animation3&lt;br /&gt;
|File:Kaup Kupershmidt csch method animation5.gif|Kaup Kupershmidt csch method animation5&lt;br /&gt;
|File:Kaup Kupershmidt sec method animation3.gif|Kaup Kupershmidt sec method animation3&lt;br /&gt;
|File:Kaup Kupershmidt sec method animation5.gif|Kaup Kupershmidt sec method animation5&lt;br /&gt;
|File:Kaup Kupershmidt sec method animation10.gif|Kaup Kupershmidt sec method animation10&lt;br /&gt;
|File:Kaup Kupershmidt sech method animation2.gif|Kaup Kupershmidt sech method animation2&lt;br /&gt;
|File:Kaup Kupershmidt sech method animation4.gif|Kaup Kupershmidt sech method animation4&lt;br /&gt;
|File:Kaup Kupershmidt sech method animation8.gif|Kaup Kupershmidt sech method animation8&lt;br /&gt;
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}}&lt;br /&gt;
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== References ==&lt;br /&gt;
* {{cite journal | first = Ashok | last = Das | coauthors = and Ziemowit Popowicz | year = 2005 | title = A nonlinearly dispersive fifth order integrable equation and its hierarchy | journal = Journal of Nonlinear Mathematical Physics | volume = 12 | issue = 1 | pages = 105–117 | url = http://www.sm.luth.se/~norbert/home_journal/electronic/121art5.pdf | format = PDF | doi = 10.2991/jnmp.2005.12.1.9 }}&lt;br /&gt;
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== External links ==&lt;br /&gt;
* {{mathworld|urlname=KupershmidtEquation|title=Kupershmidt Equation}}&lt;br /&gt;
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{{DEFAULTSORT:Kaup-Kupershmidt equation}}&lt;br /&gt;
[[Category:Partial differential equations]]&lt;br /&gt;
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{{mathanalysis-stub}}&lt;/div&gt;</summary>
		<author><name>2.233.21.81</name></author>
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