src/ZF/Ordinal.thy
author wenzelm
Thu Jan 23 10:40:21 1997 +0100 (1997-01-23)
changeset 2539 ddd22ceee8cc
parent 2469 b50b8c0eec01
child 2540 ba8311047f18
permissions -rw-r--r--
turned some consts into syntax;
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(*  Title:      ZF/Ordinal.thy
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    ID:         $Id$
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    Author:     Lawrence C Paulson, Cambridge University Computer Laboratory
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    Copyright   1994  University of Cambridge
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Ordinals in Zermelo-Fraenkel Set Theory 
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*)
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Ordinal = WF + Bool + equalities +
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consts
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  Memrel        :: i=>i
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  Transset,Ord  :: i=>o
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  "<"           :: [i,i] => o  (infixl 50) (*less than on ordinals*)
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  Limit         :: i=>o
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syntax
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  "le"          :: [i,i] => o  (infixl 50) (*less than or equals*)
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translations
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  "x le y"      == "x < succ(y)"
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defs
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  Memrel_def    "Memrel(A)   == {z: A*A . EX x y. z=<x,y> & x:y }"
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  Transset_def  "Transset(i) == ALL x:i. x<=i"
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  Ord_def       "Ord(i)      == Transset(i) & (ALL x:i. Transset(x))"
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  lt_def        "i<j         == i:j & Ord(j)"
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  Limit_def     "Limit(i)    == Ord(i) & 0<i & (ALL y. y<i --> succ(y)<i)"
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end