The Math Department at California State University, San Bernardino has help on sets at http://www.math.csusb.edu/notes/cgi/contents.cgi. Old Dominion’s site for sets is http://www.cs.odu.edu/~toida/nerzic/content/set/set_operations.html. See also http://www.jgsee.kmutt.ac.th/exell/Logic/Logic31.htm and http://www.jgsee.kmutt.ac.th/exell/Logic/Logic32.htm.

Venn diagrams are discussed at the Berkeley site http://www.stat.berkeley.edu/users/stark/Java/Venn.htm. For a biography of John Venn, see http://www-history.mcs.st-and.ac.uk/history/Mathematicians/Venn.html.

Neil Sloane at AT&T Bell Labs maintains a site http://www.research.att.com/~njas/sequences/ at which you can look up sequences.

See http://www.geocities.com/CapeCanaveral/Launchpad/2426/page136.html.

Information on decimal, octal, and hexadecimal numbers systems is available at the sites http://www.danbbs.dk/~erikoest/decimal.htm, http://www.danbbs.dk/~erikoest/octal.htm, and http://www.danbbs.dk/~erikoest/hex.htm.

The Math Department at California State University, San Bernardino has help on relations at http://www.math.csusb.edu/notes/cgi/contents.cgi. See also, http://www.jgsee.kmutt.ac.th/exell/Logic/Logic41.htm and http://www.jgsee.kmutt.ac.th/exell/Logic/Logic42.htm.

Old Dominion has help on equivalence relations at http://www.cs.odu.edu/~toida/nerzic/content/relation/eq_relation/eq_relation.html.Cut-the-Knot has further information at http://www.cut-the-knot.com/blue/equi.html.

See my own site mat_rel.pdf.

The Math Department at California State University, San Bernardino has help on functions at http://www.math.csusb.edu/notes/cgi/contents.cgi. See also Old Dominion’s site http://www.cs.odu.edu/~toida/nerzic/content/function/definitions.html.

Consult http://searchdatabase.techtarget.com/sDefinition/0,,sid13_gci212230,00.html.