n=int(input("Enter the size of matrix:"))
t=1
r=0 # r stands for row
c=0 # c stands for column
matrix=[[0 for x in range(n)]for y in range(n)] # to initialise the matrix
if n%2==0:
	k=n//2
else:
	k=int((n/2)+1)
for i in range(k):
	while c<n:
		matrix[r][c]=t
		t=t+1
		c=c+1
	r=r+1
	c=c-1
	while r<n:
		matrix[r][c]=t
		t=t+1
		r=r+1
	r=r-1
	c=c-1
	while c>=i:
		matrix[r][c]=t
		c=c-1
		t=t+1
	c=c+1
	r=r-1
	while r>i:
		matrix[r][c]=t
		t=t+1
		r=r-1
	r=r+1
	n=n-1
	c=c+1
for m in matrix:
  print(m)