N10 G90G0G54X-10.Y0
N20 M3S4500
N30 G43Z50.H1
N40 M8
N50 #1=0.5
N60 WHILE[#1LE50.]DO1
N70 #2=50.-#1
N80 #3=SQRT[2500.-[#2*#2]]
N90 G1Z-#1F20
N100 X-#3F500
N110 G2I#3
N120 #1=#1+0.1
N130 END1
N140 G0Z50.M5
N150 M30

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http://nc-corrector.inf.ua/