a<-array(0,dim=c(n,n,n))
a<-aperm(a,c(2,3,1))
a_bar_02<-apply(a,c(1,3),mean)
a_bar_2<-apply(a,2,mean)
A<-array(0,dim=c(n,n,n))
a_bar_12<-apply(a,c(2,3),mean)
for (i in 1:n){
A[i,,]<-a[i,,]-a_bar_12[,]
}
for (i in 1:n){
A[,i,]<-A[,i,]-a_bar_02[,]
}
for (i in 1:n){
for (j in 1:n){
A[i,j,]<-A[i,j,]+a_bar_2
}