src/HOL/Cardinals/Cardinal_Arithmetic.thy
changeset 55070 235c7661a96b
parent 55066 4e5ddf3162ac
child 55102 761e40ce91bc
equal deleted inserted replaced
55069:b3e44be90122 55070:235c7661a96b
     8 header {* Cardinal Arithmetic  *}
     8 header {* Cardinal Arithmetic  *}
     9 
     9 
    10 theory Cardinal_Arithmetic
    10 theory Cardinal_Arithmetic
    11 imports BNF_Cardinal_Arithmetic Cardinal_Order_Relation
    11 imports BNF_Cardinal_Arithmetic Cardinal_Order_Relation
    12 begin
    12 begin
    13 
       
    14 notation
       
    15   csum (infixr "+c" 65) and
       
    16   cprod (infixr "*c" 80) and
       
    17   cexp (infixr "^c" 90)
       
    18 
       
    19 
    13 
    20 subsection {* Binary sum *}
    14 subsection {* Binary sum *}
    21 
    15 
    22 lemma csum_Cnotzero2:
    16 lemma csum_Cnotzero2:
    23   "Cnotzero r2 \<Longrightarrow> Cnotzero (r1 +c r2)"
    17   "Cnotzero r2 \<Longrightarrow> Cnotzero (r1 +c r2)"