import sys
input = lambda : sys.stdin.readline().rstrip()

write = lambda x: sys.stdout.write(x+"\n"); writef = lambda x: print("{:.12f}".format(x))
debug = lambda x: sys.stderr.write(x+"\n")
YES="Yes"; NO="No"; pans = lambda v: print(YES if v else NO)
LI = lambda : list(map(int, input().split()))
sys.setrecursionlimit(3*10**5+10)

n = int(input())
ans = [[0]*n for _ in range(2*n-1)]
for i in range(n):
    for j in range(n+i):
        ans[j][i] = n+i
for i in range(n):
    ans[i][0] = i+1
for i in range(n, 2*n-1):
    for j in range(2*n-1-i):
        ans[i+j][j] = 2*n-i
print(len(ans))
for item in ans:
    write(" ".join(map(str, item)))