Draw overlapping circles in PostScript

circles.ps

%!PS
/inch {72 mul} def
/pagewidth { currentpagedevice /PageSize get 0 get } def
/pageheight { currentpagedevice /PageSize get 1 get } def

/cSp { 0.66 inch } def
/cRp { 6 } def

cRp {
  cRp {
    newpath
      pagewidth 2 div cSp cRp 2 div mul sub % find the center position in x
      pageheight 2 div cSp cRp 2 div mul sub % find the center position in y
    1 inch 0 360 arc stroke % draw a circle
    0 cSp translate % move to the next circle
  } repeat % draw circles vertically
  cSp 0 cSp sub cRp mul translate % reset the vertical position
} repeat % draw circles horizontally
showpage