src/HOL/Algebra/abstract/Factor.thy
changeset 17479 68a7acb5f22e
parent 13735 7de9342aca7a
child 20318 0e0ea63fe768
equal deleted inserted replaced
17478:1865064ca82a 17479:68a7acb5f22e
     2     Factorisation within a factorial domain
     2     Factorisation within a factorial domain
     3     $Id$
     3     $Id$
     4     Author: Clemens Ballarin, started 25 November 1997
     4     Author: Clemens Ballarin, started 25 November 1997
     5 *)
     5 *)
     6 
     6 
     7 Factor = Ring +
     7 theory Factor imports Ring begin
     8 
     8 
     9 consts
     9 constdefs
    10   Factorisation	:: ['a::ring, 'a list, 'a] => bool
    10   Factorisation :: "['a::ring, 'a list, 'a] => bool"
    11   (* factorisation of x into a list of irred factors and a unit u *)
    11   (* factorisation of x into a list of irred factors and a unit u *)
    12 
    12   "Factorisation x factors u ==
    13 defs
    13      x = foldr op* factors u &
    14   Factorisation_def	"Factorisation x factors u == 
    14      (ALL a : set factors. irred a) & u dvd 1"
    15                            x = foldr op* factors u &
       
    16                            (ALL a : set factors. irred a) & u dvd 1"
       
    17 
    15 
    18 end
    16 end