Will Sladek, a student at Caltech, wrote an excellent introductory paper on incompleteness in , The termite and the tower. While Will was working on his paper, I wrote a short note, Goodstein’s function, on how to compute Goodstein’s function. Please let me know of any comments of corrections to either article.

**Update: **My paper has been published.

Goodstein’s function. Revista Colombiana de Matemáticas41 (2)(2007), 381–391. MR2585906 (2011c:03139). Zbl 1156.03053.