Open problems with at most one unknown solution and some known solutions - MathOverflow most recent 30 from http://mathoverflow.net2013-06-20T08:33:22Zhttp://mathoverflow.net/feeds/question/101758http://www.creativecommons.org/licenses/by-nc/2.5/rdfhttp://mathoverflow.net/questions/101758/open-problems-with-at-most-one-unknown-solution-and-some-known-solutionsOpen problems with at most one unknown solution and some known solutionsjoro2012-07-09T09:39:03Z2012-07-09T09:39:03Z
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<p>What are examples of open problems with at most one unknown solution and some known solutions?</p>
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<p>Some examples:</p>
<p>There is at most one more <a href="https://en.wikipedia.org/wiki/Idoneal_number" rel="nofollow">Idoneal number</a>.</p>
<p><a href="http://math.ucalgary.ca/~ramollin/cn2frqfrdt.pdf" rel="nofollow">CLASS NUMBER TWO FOR REAL QUADRATIC FIELDS OF RICHAUD-DEGERT TYPE</a>: The following are equivalent (a) $h_\Delta=2$ (b) $\Delta$ s one of the following values, with one GRH-ruled-out exception: {85, 165, 221, 285, ...</p>
<p>Trying the make the question well defined the problems shouldn't be artificially constructed.</p>
<p>Preferably the missing solution shouldn't be ruled out by some plausible conjecture.</p>