Counting n-gons
Richard Guy
rkg at cpsc.ucalgary.ca
Wed Oct 25 16:15:37 CEST 2006
max area of 1,1,2,2 quad is cyclic, a kite
formed by 2 right triangles with legs 1 & 2,
area 2. R.
On Tue, 24 Oct 2006, Jonathan Post wrote:
> Dr. George Hockney (ex-Fermilab, now JPL)
> responded to my suggestion that
> the representative of each equivalence class of
> deformed polygons with the
> same edge-sequences be that with largest area
> that: (1) this might not be
> unique, and (2) that the maximum area (1, 1, 2, 2)
> quadrilateral is the
> (1+1=2, 2, 2) equilateral triangle of area sqrt 3,
> where the two edges of
> length 1 make an angle of 180 degrees, and asks if
> that equilateral triangle
> with a vertex in the middle of its side is really
> a quadrilateral, or is
> that another ambiguity in equivalence of polygons
> under geometrical
> similarity? He is also dubious that the
> integer-edged polygonal knots in R^3
> are really polygons, as I've stated.
>
> I agree with David Wilson's sequence. What about
> a sequence table of
> maximal areas of all simple integer-sided k-gons
> of perimeter n?
>
> -- Jonathan Vos Post
>
> On 10/24/06, David Wilson
> <davidwwilson at comcast.net> wrote:
>>
>> And we should have a sequence that counts all
>> simple integer-sided
>> polygons
>> of perimeter n. Depending on exactly what we are
>> counting, the sequence
>> might go:
>>
>> a(3) = 1, the 1-1-1 triangle.
>> a(4) = 1, the 1-1-1-1 quadrilateral.
>> a(5) = 3, the 1-2-2 triangle, 1-1-1-2
>> quadrilateral, the 1-1-1-1-1
>> pentagon.
>>
>> etc.
>>
>>
>
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