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#1 Re: Help Me ! » Calculate the total number of `internal fields` in a regular polygon » 2014-02-13 06:27:44

This is what happens when a smart aleck ex-musician tries to do algebra. If n-17, then if I interpret the formula correctly,
24-714+152881-1061208+83521 = 825496 /24 = -34,394.667,

Similarly, if n=7, {24-294+25921-74088+2401 = -46036}/24 = -1.918.1667.
What happened to 50?

#2 Re: Help Me ! » Calculate the total number of `internal fields` in a regular polygon » 2014-02-12 09:05:40

Hi, bobbym,

I started out calculating the number of lines possible between 1-2-3-4-5 . . . points. I arrived at 0-1-3-6-10-15 when including the sides and diagonals of what turn out to be drawn regular polygons. The progression became apparent. So far, I cannot see the progression represented by the progression of "internal fields." (Is that what to call them?) Nor have I yet been able to devise a formula for solving it. (Still stuck with counting - or as you observed, miscounting them.)

#3 Help Me ! » Calculate the total number of `internal fields` in a regular polygon » 2014-02-12 07:00:24

JT_OO400
Replies: 11

Question: How do I calculate the total number of `internal fields` in a regular polygon?

(Visually, triangle = 1, rectangle = 4, pentagon = 11, heptagon - 45.)

1) What is the `progression` of the numbers of internal fields (Is that the correct term/), and 2) what is the formula for calculation the number, based on the number of sides?

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