3,4,5; 5,12,13; and then?

13,84,85; 85,132,157; and then....?

157, and two numbers that are over three thousand (beyond my Excel number crunching patience).

It would probably make an interresting spiral.

Or not. It may be that there do not exist any two integers for whose squared difference equal 157 squared. It souldn't be to hard too determine, but even if they exist, a<b, who's to say it'll work for b, etc.?