\ The following program doesn't actually run; you need to give it only
\ one of the non-commented lines:

\ Roll xkx, for four or less exploding dice.  4k2 given

sum (largest 2 (4#(sum (let x=d10 in repeat ((count =10 x)#d10)))))

\ Roll xkx, for five or more rolled dice, exploding only those kept.
\ 7k3 given

sum (let x=largest 3 (7#d10) in repeat ((count =10 x)#d10))