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r.svg(filename='"Rplots.svg"',width=6,height=6,onefile=True,
family='"times"',bg='"black"',pointsize=10,
antialias=r.c('"default"','"none"','"gray"','"subpixel"'))
r.eval("""
a<-sample(5:11,1); b<-sample(13:19,1)
c<-2*sample(3:10,1); n<-sample(18:144,1)
t<-seq(1,2*n+1,.1)
col=rgb(runif(1),runif(1),1,alpha=.3)
plot(0,0,type='n',xlim=c(-3,3),ylim=c(-3,3))
for (k in 1:c){
fx<-sin(pi*t/n+k*2*pi/c)-
sin(a*pi*t/n+k*2*pi/c)+sin(b*pi*t/n+k*2*pi/c)
fy<-cos(pi*t/n+k*2*pi/c)+
cos(a*pi*t/n+k*2*pi/c)+cos(b*pi*t/n+k*2*pi/c)
polygon(fx,fy,lwd=1.5,border=col,xlab='',ylab='',
xlim=c(-3,3),ylim=c(-3,3))
par(new=TRUE)}
paste0('a = ',a,'; b = ',b,'; c = ',c,'; n = ',n)
""")
r.dev_off()