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

sys.setrecursionlimit(2*10**5+10)
write = lambda x: sys.stdout.write(x+"\n")
debug = lambda x: sys.stderr.write(x+"\n")

n = int(input())
dxy = [
    [3,0],[-3,0],
    [0,3],[0,-3],
    [2,3],[3,2],
    [-2,3],[-3,2],
    [2,-3],[3,-2],
    [-2,-3],[-3,-2]
]
def sub(n):
    s = set()
    v = (0,0)
    s = [v]
    for _ in range(n):
        ns = set()
        for v in s:
            xx,yy = v
            for x,y in dxy:
                ns.add((x+xx,y+yy))
        s = ns
    return (s)
if n<7:
    ans = len(sub(n))
elif n%2==0:
    ans = ((6*n+1)**2 - 1)//2 - (n**2) + 1
else:
    ans = ((6*n+1)**2 - 1)//2 - (n**2-1)
print(ans)