You must choose a number less than or equal to 50 for 
the number of desired intervals.

An example will help to illustrate the use of the term interval.
If one chooses 3  intervals between:
Start Date:            2009,2,1,0,0,10.0
Stop Date and Time:    2009,4,1,0,0,10.0

Then the output should have 3 intervals and 4 epochs bracketing 
those 3 intervals. I.e.,

  MJD       MJD fraction       YR     Month  Day     Hour   Min   Sec
  54863    1.15740741E-04    2009     2      1       0       0   10.0E+01
        <---   I N T E R V A L (1)  --->
  54864    1.15740741E-04    2009     2      2       0       0   10.0E+01
        <---   I N T E R V A L (2)  --->
  54865    1.15740741E-04    2009     2      3       0       0   10.0E+01
        <---   I N T E R V A L (3)  --->
  54866    1.15740741E-04    2009     2      4       0       0   10.0E+01


NOTE: It was requested that the last epoch be dropped from the following selection:
Output containing eqn equinoxes-polar motion, polar motion,
precession-nutation, ut1-utc offset and slope, and epoch:
And so, for the selection below:
Start Date:            2005,1,5,0,0,0.0
Stop Date and Time:    2005,1,8,0,0,0.0
Nintervals:            3

The result would be:
     YR     Month  Day     Hour   Min   Sec
   2005      1      5       12     0   0.0E+01
        <---   I N T E R V A L (1)  --->
   2005      1      6       12     0   0.0E+01
        <---   I N T E R V A L (2)  --->
   2005      1      7       12     0   0.0E+01
        <---   I N T E R V A L (3)  --->