10 GRAPHICS 9
15 SETCOLOR 4,15,0
20 FOR Y=55 TO 0 STEP -10
30 FOR X=0 TO 24
40 C=X:IF X>11 THEN C=24-X
45 C=C+3
50 Z=Y+(X)
55 D=INT(SQR(144-(X-12)*(X-12)))/2
57 COLOR 15-C
58 PLOT Z,Y+7-D
60 DRAWTO Z,Y+7+D
70 COLOR C
80 DRAWTO Z,180-Y+D
180 NEXT X
190 NEXT Y
200 GOTO 200