matita/contribs/RELATIONAL-ARITHMETICS/add_defs.ma

   1 (**************************************************************************)
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   3 (*      ||M||                                                             *)
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  13 (**************************************************************************)
  14
  15 set "baseuri" "cic:/matita/RELATIONAL-ARITHMETICS/add_defs".
  16
  17 include "nat_defs.ma".
  18
  19 inductive add (p:nat): nat \to nat \to Prop \def
  20    | add_O_2: add p O p
  21    | add_S_2: \forall q, r. add p q r \to add p (S q) (S r).