User:Noosfractal/Unsolved problems in mathematics

Unsolved problems

• Is the Euler-Mascheroni constant a rational number?
• Are there any odd perfect numbers?

Sites listing unsolved problems

• MathWorld page on the topic - also references a number of books.
• Listing of pages in MathWorld's unsolved problems category
• Math/Research/Open_Problems/ at the Open Directory Project - with subsections on open problems in analysis, combinatorics, dynaical systems, geometry, graph theory, number theory and topology.
• The Open Problems Project at Smith
• Kirby's famous 360 page list of open problems in Topology
• Archive of the Open Problems column of the SIAM Newsletter
• Kimberling's open problems with rewards
• More open problems with rewards

Sites referenced by MathWorld

Eppstein, D. "Open Problems." http://www.ics.uci.edu/~eppstein/junkyard/open.html.

MathPages. "Most Wanted List of Elementary Unsolved Problems." http://www.mathpages.com/home/mwlist.htm.

West, D. "Open Problems--Graph Theory and Combinatorics." http://www.math.uiuc.edu/~west/openp/.

Books discussing unsolved problems

• . ISBN 156881111X. {{cite book}}: Missing or empty |title= (help); Unknown parameter |Author= ignored (|author= suggested) (help); Unknown parameter |Publisher= ignored (|publisher= suggested) (help); Unknown parameter |Title= ignored (|title= suggested) (help); Unknown parameter |Year= ignored (|year= suggested) (help)
• . ISBN 0387975063. {{cite book}}: Missing or empty |title= (help); Unknown parameter |Author= ignored (|author= suggested) (help); Unknown parameter |Publisher= ignored (|publisher= suggested) (help); Unknown parameter |Title= ignored (|title= suggested) (help); Unknown parameter |Year= ignored (|year= suggested) (help)
• . ISBN 0387208607. {{cite book}}: Missing or empty |title= (help); Unknown parameter |Author= ignored (|author= suggested) (help); Unknown parameter |Publisher= ignored (|publisher= suggested) (help); Unknown parameter |Title= ignored (|title= suggested) (help); Unknown parameter |Year= ignored (|year= suggested) (help)
• . ISBN 0883853159. {{cite book}}: Missing or empty |title= (help); Unknown parameter |Author= ignored (|author= suggested) (help); Unknown parameter |Publisher= ignored (|publisher= suggested) (help); Unknown parameter |Title= ignored (|title= suggested) (help); Unknown parameter |Year= ignored (|year= suggested) (help)
• . ISBN 187958574X. {{cite book}}: Missing or empty |title= (help); Unknown parameter |Author= ignored (|author= suggested) (help); Unknown parameter |Publisher= ignored (|publisher= suggested) (help); Unknown parameter |Title= ignored (|title= suggested) (help); Unknown parameter |Year= ignored (|year= suggested) (help)