src/HOL/ex/NatSum.thy
author paulson
Tue, 16 Jul 1996 15:49:46 +0200
changeset 1868 836950047d85
parent 1476 608483c2122a
child 3269 eca2a3634acd
permissions -rw-r--r--
Put in minimal simpset to avoid excessive simplification, just as in revision 1.9 of HOL/indrule.ML

(*  Title:      HOL/ex/natsum.thy
    ID:         $Id$
    Author:     Tobias Nipkow
    Copyright   1994 TU Muenchen

A summation operator. sum(f,n+1) is the sum of all f(i), i=0...n.
*)

NatSum = Arith +
consts sum     :: [nat=>nat, nat] => nat
rules  sum_0      "sum f 0 = 0"
       sum_Suc    "sum f (Suc n) = f(n) + sum f n"
end