ot -- Option Tab

        range                        syntax
         1,$                ot[[[+]integer [+]integer]]


        "ot+3" sets the spacing between tab stops.  The  default  value
        when  'se'  comes  up  is 3.  Typing "ot" by itself causes the
        current value of the parameter to be displayed.  As an example
        of how tabs are spaced out, if ot+6 is in effect, tab stops are
        at 7, 13, 19, etc.
        Variable  tabs can be set by typing "ot 5 13 24 ..  ".  if you
        do not prefer equally spaced ones.

        See also "hof".
        For general information about the option command, type "ho".
        For more about the use of tab stops, type "hmotion".