n=int(input())
m=2*n-1
ans=[[0]*n for i in range(m)]
for j in range(n):
  if j==n-1:
    for i in range(m):
      ans[i][j]=m
    continue
  if j%2:
    for i in range(j+1):
      ans[i][j]=j+1
    for i in range(j+1,m):
      ans[i][j]=m-j-1
  else:
    for i in range(m-j-1):
      ans[i][j]=m-j-1
    for i in range(m-j-1,m):
      ans[i][j]=j+1

print(m)
for i in ans:
  print(*i)