[GAP Forum] how TzGo worked with us

[Igor Korepanov]

And still one more comment: we calculated yesterday the fundamental group of the 4-dimensional torus, which is, as everybody knows, the *abelian* group with 4 generators. That is, the Fp Group with 4 generators and 6 relation of type   a * b * a^-1 * b^-1 .

And all that was happily present in our GAP result, but besides that, there was one more redundant relation which we could derive manually from 6 others, but the TzGo algorithm apparently could not!

We used some stuff of our own to define this fundamental group and then the usual TzGo command to simplify it.

Of course I've heard of undecidable problems and stuff (as I am currently employed as a university lecturer, like many people on this forum). But this particular problem must be decidable (here I searched Internet for a suitable English interjection like "er?" to end my letter, but found only some strange "Ekh-ma" http://en.wikipedia.org/wiki/Ekh_%28expression%29 ) ?

Best wishes,

Igor