src/HOL/Algebra/abstract/Factor.thy
changeset 13735 7de9342aca7a
parent 7998 3d0c34795831
child 17479 68a7acb5f22e
equal deleted inserted replaced
13734:50dcee1c509e 13735:7de9342aca7a
     5 *)
     5 *)
     6 
     6 
     7 Factor = Ring +
     7 Factor = Ring +
     8 
     8 
     9 consts
     9 consts
    10   Factorisation	:: ['a::ringS, '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 
    13 defs
    13 defs
    14   Factorisation_def	"Factorisation x factors u == 
    14   Factorisation_def	"Factorisation x factors u == 
    15                            x = foldr op* factors u &
    15                            x = foldr op* factors u &
    16                            (ALL a : set factors. irred a) & u dvd <1>"
    16                            (ALL a : set factors. irred a) & u dvd 1"
    17 
    17 
    18 end
    18 end