%! Not DSC compliant

/un {
    /c exch def
    0
    {
        1 add
        dup
        [ 2 3 5 ] {
            /k exch def
            {
                dup k mod 0 eq {
                    k div cvi
                } {
                    exit
                } ifelse
            } loop
        } forall
        1 eq {
            /c c 1 sub def
        } if
        c 0 le {
            exit
        } if
    } loop
} def

/str 50 string def
/fs 12 def
/Helvetica findfont
fs scalefont setfont
20 750 translate
/line 0 def
/testnum 1 def

/disptest {
    0 line moveto testnum str cvs show (.) show
    dup
    50 line moveto str cvs show
    un
    dup
    100 line moveto str cvs show
    eq { (Pass) } { (FAIL) } ifelse
    150 line moveto show
    /line line fs 2 mul sub def
    /testnum testnum 1 add def
} def

8 7 disptest
12 10 disptest
16200 200 disptest

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