set.seed(423)
n<-20
al<-3
Nrep<-1000
nboot<-10000
tvec<-rep(0,nboot)
ico<-0
for(irep in 1:Nrep){
	X<-rgamma(n,al,1)
	for(i in 1:nboot){
		tvec[i]<-mean(sample(X,size=n,rep=T))
	}
	qv<-quantile(tvec,prob=c(0.025,0.975))
	if(al >= qv[1] & al <= qv[2]){ico<-ico+1}
}
print(ico/Nrep)