The java distance program was translated from my old C program into a java program by Teresinha Kawasaki. It will find all integers t such that d_t(S(a,b), S(u,v) = 1 (except possibley t = 1, -1) for any pair of 4-plats entered into the program. At the moment, one cannot yet input S(0,1). If you need this calculation, please e-mail me. This program is not yet in user friendly format, so if you have any questions, comments, difficulties using it, or to report any bugs, please e-mail me at darcy@math.utexas.edu

Given a, b, u, v, a new C-program solves for U, t, w in the unoriented tangle equations

N(U + 0) = N(a/b) and N(U + t/w) = N(u/v)

Note that if t = -1, +1, then the program does not find all solutions. Namely, it misses solutions where U is not ambient isotopic to a sum of rational tangles.

Given a, b, u, v, another C-program solves for U, t, w in the oriented tangle equations

N(U + 0) = N(a/b) and N(U + t/w) = N(u/v)

Again note that if t = -1, +1, then the program does not find all solutions. Namely, it misses solutions where U is not ambient isotopic to a sum of rational tangles.

A java version of the above two programs is currently in development

Please report all bugs to darcy@utdallas.edu