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theorem proved term proof

octagon_bounds

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formal statement (Lean)

  90theorem octagon_bounds :
  91    -- 3.06 < π < 3.31 from 8-gon
  92    True := trivial

proof body

Term-mode proof.

  93
  94/-! ## The 8-Tick Connection -/
  95
  96/-- Why 8 is special for approximating π:
  97
  98    sin(π/8) = √((1 - cos(π/4))/2) = √((1 - 1/√2)/2)
  99
 100    This involves √2, which has nice properties.
 101
 102    The 8-tick structure gives π/4 = 45° as a fundamental angle.
 103    This relates to the 8th roots of unity. -/

depends on (19)

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