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  LXXV. 
  The 
  Summation 
  of 
  a 
  Type 
  of 
  a 
  Family 
  of 
  

   Trigonometric 
  Series. 
  By 
  I. 
  J. 
  Schwatt 
  *.j 
  

  

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  1 
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  To 
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  wherein 
  @ 
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  is 
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  hi\\ 
  roots 
  of 
  unity. 
  

   * 
  Communicated 
  by 
  the 
  Author. 
  

  

  