Looking on the internet deeply has found these results:

keen on mathematics is the most popular phrase on the web.

keen to mathematics 11 results on the web	keen on mathematics 113,600 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
Go to mathematics memory activities against Tux When it comes to mathematics, he is second to none in his class. For example, projects were dealing with access to mathematics, music or school books through the use of computers providing interactive Braille or voice interfaces. It is therefore practically impossible to reduce all of this to mathematics. With specific regard to mathematics, science and technology: And on the handful of occasions I have tackled a case which pertained to mathematics... John's really keen to have you on. So keen to fight and to solve affronts...	It doesn't look like this phrase is very popular! The search could not find any examples on the internet.

keen to mathematics

11 results on the web

keen on mathematics

113,600 results on the web

More popular!

Go to mathematics memory activities against Tux
When it comes to mathematics, he is second to none in his class.
For example, projects were dealing with access to mathematics, music or school books through the use of computers providing interactive Braille or voice interfaces.
It is therefore practically impossible to reduce all of this to mathematics.
With specific regard to mathematics, science and technology:
And on the handful of occasions I have tackled a case which pertained to mathematics...
John's really keen to have you on.
So keen to fight and to solve affronts...

It doesn't look like this phrase is very popular! The search could not find any examples on the internet.