author | wenzelm |
Thu, 03 Aug 2006 17:30:43 +0200 | |
changeset 20335 | b5eca86ef9cc |
parent 20318 | 0e0ea63fe768 |
child 21423 | 6cdd0589aa73 |
permissions | -rw-r--r-- |
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(* |
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Factorisation within a factorial domain |
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$Id$ |
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Author: Clemens Ballarin, started 25 November 1997 |
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*) |
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20318
0e0ea63fe768
Restructured algebra library, added ideals and quotient rings.
ballarin
parents:
17479
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changeset
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theory Factor imports Ring2 begin |
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constdefs |
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Factorisation :: "['a::ring, 'a list, 'a] => bool" |
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(* factorisation of x into a list of irred factors and a unit u *) |
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"Factorisation x factors u == |
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x = foldr op* factors u & |
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(ALL a : set factors. irred a) & u dvd 1" |
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end |