[seqfan] Re: Reference Help?

[brad klee]

> But I found an email of a Stephan Herfurtner. 
> He is still living at the
> exact same address as the one in his thesis.
> Perhaps he does know something more on the topic.

The Kodaira notation is already very suggestive what could 
possibly happen when allowing a higher genus: 

https://en.wikipedia.org/wiki/Elliptic_surface

Unfortunately this type of combinatorics wasn't part of my
physics curriculum, to say the least. It's still a ways up 
from where I can get to easily. 

Proofs about transforming between curve models have been very 
difficult to find, and there is an added difficulty when the 
underlying manifold is itself changing. Maybe the practice needs
more of a focus put on "Reimann uniformization"? 

Another example of missing parameters covered by Herfurtner 
is A005258. This seq. was known before 1990 (even though the 
Beauville article is very terse and doesn't cite Apéry). 
Also, Beukers gave another model for integral definitions. 

The flexibility of these sequences to appear in different domains 
does cause me to wonder what other models are out there, perhaps 
making it easier to see what the geometry actually looks like. 

Thanks for the emails, I will try to contact the authors. 
I'm sure that interpol, the ABC, and XY&Y will be happy to see 
us all getting along again.  

Cheers,

--Brad