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fixed some regressions
[helm.git] / helm / software / matita / contribs / dama / dama_duality / tend.ma
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3 (*      ||M||                                                             *)
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11 (*        v         GNU General Public License Version 2                  *)
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14
15 include "sequence.ma".
16 include "metric_space.ma".
17 include "nat/orders.ma".
18
19 definition tends0 ≝ 
20   λO:pogroup.λs:sequence O.∀e:O.0 < e → ∃N.∀n.N < n → -e < s n ∧ s n < e.
21
22 definition d2s ≝ 
23   λR.λms:metric_space R.λs:sequence ms.λk.λn. δ (s n) k.
24
25 notation "s ⇝ x" non associative with precedence 50 for @{'tends $s $x}.
26 interpretation "tends to" 'tends s x = (tends0 _ (d2s _ _ s x)).
27