src/HOL/ex/NatSum.thy
author clasohm
Mon, 05 Feb 1996 21:29:06 +0100
changeset 1476 608483c2122a
parent 1376 92f83b9d17e1
child 3269 eca2a3634acd
permissions -rw-r--r--
expanded tabs; incorporated Konrad's changes

(*  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