Date: Sep 21, 2004 11:26 AM
Subject: Re: [CALC-REFORM:3238] induction

Re: Mark Bridger's request for better induction\well-ordering examples.

The three "archetypes" found in most intro-to-proof texts are
1. Summation\product formulas.
2. Inequalities.
3. Divisibility propositions.
Some are useful, most are at least historically interesting.
As already pointed out, lack of discovery is common to these examples.

Good sources: _A Transition to Advanced Mathematics_, Smith-Eggen-St. Andre_
_Chapter Zero_, Carol Schumacher
_Introduction to Mathematical Structures_, Steve Galovich

Another collection of very interesting examples have origin in general
position arguments and discrete mathematics. Here are a couple of examples:

1. Every partition of the plane by a finite number of straight lines
can be two-colored.
2. In a round-robin tournament (no ties) a _top player_ is a player#1
who, for every other player#2, either beats that player#2 or beats
some other player#3 who beats that player#2. Every such tournament
with a finite number of players has at a top player.
3. Any 2^n-by-2^n chessboard with one deleted square can be tiled using
2-by-2 with one square deleted tiles.
4. A jig-saw puzzle is assembled by successively joining pieces together
into blocks. A move is the joining of two pieces to form a block, the
joining of a piece to an existing block, and the joining of two exist-
ing blocks. Every n-piece puzzle requires exactly n-1 moves.

Although not calculus. I will post this to the group on the odd chance that
of interest to others than just Mark.

Dale M. Rohm