A Texas banker is upping the ante to $1 million for whoever solves a tricky problem that's been dogging mathematicians since the 1980s.

The Providence, R.I.-based American Mathematical Society on Tuesday said $1 million will be awarded for the publication of a solution to the Beal Conjecture number theory problem.

Dallas banker D. Andrew Beal first offered the Beal Prize in 1997 for $5,000. Over the years, the amount has grown.

American Mathematical Society spokesman Michael Breen says a solution is more difficult than the one for a related problem, Fermat's Last Theorem, which didn't have a published solution for hundreds of years.

Beal is a self-taught mathematician and says he wants to inspire young people to pursue math and science.