vigenere[ "I came Isaw I conquered", "Egypt"]

  {{8, 2, 0, 12, 4}, {8, 18, 0, 22, 8}, 

    {2, 14, 13, 16, 20}, {4, 17, 4, 3, 15}}

  {4, 6, 24, 15, 19}

  

  

  ;[o]

  {{8, 2, 0, 12, 4}, {8, 18, 0, 22, 8}, 

    {2, 14, 13, 16, 20}, {4, 17, 4, 3, 15}}

  {4, 6, 24, 15, 19}

Out[22]=

  miybxmyylbgulfnixcsi

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