| author | paulson | 
| Wed, 23 Jul 1997 11:52:22 +0200 | |
| changeset 3564 | f886dbd91ee5 | 
| parent 3413 | c1f63cc3a768 | 
| child 5101 | 52e7c75acfe6 | 
| permissions | -rw-r--r-- | 
| 1475 | 1 | (* Title: HOL/Finite.thy | 
| 923 | 2 | ID: $Id$ | 
| 1531 | 3 | Author: Lawrence C Paulson & Tobias Nipkow | 
| 4 | Copyright 1995 University of Cambridge & TU Muenchen | |
| 923 | 5 | |
| 1531 | 6 | Finite sets and their cardinality | 
| 923 | 7 | *) | 
| 8 | ||
| 3389 
3150eba724a1
New theorem about the cardinality of the powerset (uses exponentiation)
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changeset | 9 | Finite = Divides + Power + | 
| 1531 | 10 | |
| 3413 
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Finite.ML Finite.thy: Replaced `finite subset of' by mere `finite'.
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changeset | 11 | consts Finites :: 'a set set | 
| 923 | 12 | |
| 3413 
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Finite.ML Finite.thy: Replaced `finite subset of' by mere `finite'.
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changeset | 13 | inductive "Finites" | 
| 923 | 14 | intrs | 
| 3413 
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Finite.ML Finite.thy: Replaced `finite subset of' by mere `finite'.
 nipkow parents: 
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changeset | 15 |     emptyI  "{} : Finites"
 | 
| 
c1f63cc3a768
Finite.ML Finite.thy: Replaced `finite subset of' by mere `finite'.
 nipkow parents: 
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changeset | 16 | insertI "A : Finites ==> insert a A : Finites" | 
| 
c1f63cc3a768
Finite.ML Finite.thy: Replaced `finite subset of' by mere `finite'.
 nipkow parents: 
3389diff
changeset | 17 | |
| 
c1f63cc3a768
Finite.ML Finite.thy: Replaced `finite subset of' by mere `finite'.
 nipkow parents: 
3389diff
changeset | 18 | syntax finite :: 'a set => bool | 
| 
c1f63cc3a768
Finite.ML Finite.thy: Replaced `finite subset of' by mere `finite'.
 nipkow parents: 
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changeset | 19 | translations "finite A" == "A : Finites" | 
| 923 | 20 | |
| 1556 | 21 | constdefs | 
| 22 | card :: 'a set => nat | |
| 23 |   "card A == LEAST n. ? f. A = {f i |i. i<n}"
 | |
| 1531 | 24 | |
| 923 | 25 | end |