# Subject pages attached to craig:topic/mathematics

mathematics
 1 Eric Weisstein's World of Mathematics "MathWorld is a convenient, comprehensive, and interactive mathematics encyclopedia intended for students, educators, math enthusiasts, and researchers." URL: http://mathworld.wolfram.com 2 The New Mathwright Library The New Mathwright Library is a free collection of more than 110 interactive mathematics and science books. These electronic books, developed by math and science teachers (and students), have been used in Web-based mathematics courses taught at universities and secondary schools. URL: http://www.mathwright.com 3 Favorite Mathematical Constants This website is a collection of more than 70 essays and a Table of Mathematical Constants. For each constant, the table provides its value, a brief description, and a link to one of the essays. Some of the material can be downloaded in postscript form. URL: http://www.mathsoft.com/asolve/constant/constant.html 4 Unsolved Mathematics Problems This evolving collection of unsolved mathematics problems is not systematic or complete; it is only an eclectic gathering of questions and partial answers which have come to my attention over the years. URL: http://www.mathsoft.com/asolve/index.html 5 Mathstories.com The goal of this web site is to help grade school children improve their math problem-solving skills. This site started out as only a few pages, but it has grown to hundreds of pages with over 2,000 math word problems for children to enjoy! URL: http://www.mathstories.com 6 On-Line Encyclopedia of Integer Sequences At the present time the table contains around 50000 sequences. 5487 of the best of these sequences were published in 1995 in The Encyclopedia of Integer Sequences, by me and Simon Plouffe. URL: http://www.research.att.com/~njas/sequences 7 Important Formulae for Complex Numbers Has Lorenz attractors, Henon Map, etc. URL: http://www.lifesmith.com/technical.html 8 JOMA - Journal of Online Mathematics and its Applications Published by the Mathematical Association of America, this new online journal aims to advance the mathematical sciences, especially at the college level, by promoting effective teaching, fostering scholarship, and "making modern tools, curricula, and active learning environments more accessible to students and teachers everywhere." URL: http://www.joma.org/ 9 Math Forum Internet Mathematics Library: Hot Spot of the Month Monthly listing of one excellent math website for students. URL: http://mathforum.org/library/hotspots/00.html 10 Inverse Symbolic Calculator [java applet] You input an approximate real number and the search engine will search for a symbolic number that matches or is close to the search number. URL: http://www.cecm.sfu.ca/projects/ISC/ISCmain.html
mathematics/combinatorics
 11 Combinatorics Dedekind's Problem Generating Function For Eulerian Numbers Permutation Loops Polyomino Enumerations Powers of Primes Dividing Factorials The Dartboard Sequence Binary Games 414298141056 Quarto Draws Suffice!, etc. URL: http://www.seanet.com/~ksbrown/icombina.htm 12 Cumulative Permutation Sequences Let p1, p2, ...,pk (where k = n!) denote the permutations of n elements, and let "*" denote composition. (For example, pi*pj signifies the permutation given by first applying pj, and then applying pi.) Of course, the n! permutations can be ordered in (n!)! different ways. URL: http://www.seanet.com/~ksbrown/kmath098.htm 13 Permutation Loops Suppose a,b,c,d,e are elements of a group. We'll call a circular arrangement of such elements a "loop". For example, we might choose to arrange those elements in alphabetical order, giving the loop {abcde}, where the last element is understood to wrap around to the first. Note that {abcde} and {eabcd} are both valid representations of the same loop, since they are just rotations of each other. URL: http://www.seanet.com/~ksbrown/kmath031.htm 14 double cosets Thus when n is odd, the formula is 1/(2n)^2 { n^2 ((n-1)/2)! 2^((n-1)/2) + sum{d|n} sigma(d)^2 (n/d)! d^(n/d)}. So for even n, the formula is 1/(2n)^2 {2(n/2)(n/2)!2^(n/2)+(n/2)^2(n/2)!2^(n/2) +(n/2)^2(n/2-1)!2^(n/2) +sum{d|n} sigma(d)^2 (n/d)! d^(n/d)} =1/(2n)^2 {2^(n/2)(n/2)![n+(n/2)^2+n/2]+sum{d|n}...} =1/(2n)^2 {2^(n/2)(n/2)!(n/2)(n/2+3) +sum{d|n} sigma(d)^2 (n/d)! d^(n/d)}. URL: http://members.nbci.com/Polytope/double-cosets
mathematics/computing
 15 Sal - scientific Applications on Linux SAL (Scientific Applications on Linux) is a collection of information and links to software that will be of interest to scientists and engineers. The broad coverage of Linux applications will also benefit the whole Linux/Unix community. There are currently 2,637 entries in SAL. URL: http://sal.kachinatech.com 16 Numerical Recipies [Universal Library] The Numerical Recipes (NR) books are developed by Numerical Recipes Software and published by Cambridge University Press. URL: http://www.nr.com/ 17 GNU Scientific Library [manual] Mathematical functions including bessel I0 function for C programming. URL: http://sources.redhat.com/gsl/
mathematics/geometry/polyhedra
 18 Virtual Polyhedra: The Encyclopedia of Polyhedra This site is a free self-contained easy-to-explore tutorial, reference work, and object library for people interested in polyhedra. You may choose to simply view the virtual objects for their timeless, serene aesthetics, or to read the related mathematical background material at various levels of depth. URL: http://www.georgehart.com/virtual-polyhedra/vp.html
mathematics/graph
 19 Graph Paper color and black-and white types. URL: http://www.mathematicshelpcentral.com/graph_paper.htm 20 Create your own graph paper Output in PDF format. URL: http://www.incompetech.com/beta/plainGraphPaper/create.pl
mathematics/information_theory
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