src/HOL/RelPow.thy

pdf: generate thumbnails if ISABELLE_THUMBPDF set;

(*  Title:      HOL/RelPow.thy
    ID:         $Id$
    Author:     Tobias Nipkow
    Copyright   1996  TU Muenchen

R^n = R O ... O R, the n-fold composition of R
*)

RelPow = Nat +

instance
  set :: (term) {power}   (* only ('a * 'a) set should be in power! *)

primrec
  "R^0 = Id"
  "R^(Suc n) = R O (R^n)"

end