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    Re: Bris does not work
    From: Bill Noyce
    Date: 2012 Jul 27, 12:15 -0700

    Alex wrote:

    > Still I don't understand these numbers (bright, dim)=(3,5).
    > We have 3 surfaces, say 1,2,3, counting from Sun to the eye.
    > Then the three bright images must occur when two reflections
    > happen, that is (2,1), (3,1) and (3,2). Now the dim ones must
    > be due to 4 reflections for which we have these possibilities:
    > (2,1,2,1), (2,1,3,1), (2,1,3,2), (3,1,2,1), (3,1,3,1), (3,1,3,2), (3,2,3,1),
    > (3,2,3,2). So there should be 3 bright and 8 dim images
    > Why then we have only 5 dim?

    I think (2,1,3,1) produces the same image as (3,1,2,1).
    Similarly for (3,1,3,2) and (3,2,3,2). And I think (2,1,3,2)
    produces the same image as (3,1). Does that explain it?
    -- Bill N.
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