KnotJob

KnotJob is a Java programme designed to calculate knot invariants centered around Khovanov homology. The current version () can calculate

• even and odd Khovanov homology.
• Rasmussen's S-invariants for fields up to characteristic 211 and an integral version.
• Lipshitz-Sarkar's refinements of the mod 2 S-invariant for first and second Steenrod squares (even and odd).
• Dunfield-Lipshitz-Schütz refinements of the mod 2 and integral S-invariant.
• The second Steenrod Square for the Lipshitz-Sarkar stable Khovanov homotopy type, and an odd version.
• The Bar Natan-Lee-Turner spectral sequence for fields up to characteristic 211.
• The Alexander and Jones polynomials.
• The signature and the determinant.

It can be downloaded here. It requires Java 17 to run, and the awt.desktop class which doesn't seem to run everywhere (such as my office Linux computer). This can be fixed by commenting out a few lines in the source code. Instructions for this are in the zip-file. There is an older version which runs on Java 8 here, but with fewer knot invariants. Again the current version can be made to work on Java 8 with only a few changes in the source code.
I used to have more older versions on this website, but have removed them now. This includes SKnotJob and TKnotJob, which are incorporated into the latest version.