Is there a rule in the ( atan(x) confrac,fraction,12 ==> ) in Mathcad ?

[lvl107]

  Hello, Everyone.

  The Question : Is there a rule in the sequence of numbers : 1, 3 , 5, 28, 81, 704  ?

         Thanks in advance for your time and help.

                Regards.

[-MFra- · Accepted solution]

[lvl107]

  Oh... , Many thanks, P.M.

     Best Regards.