687 B | 687 chars
import sys
from math import sqrt, pi, sin, factorial, ceil, floor
from decimal import Decimal
BLANK = " "
inp = input
# inp = lambda : sys.stdin.readline()[:-1].strip()
mii = lambda x = BLANK : [*map(int,inp().split(x))]
mfi = lambda x = BLANK : [*map(float,inp().split(x))]
ii = lambda : int(inp())
fi = lambda : float(inp())
p = print
def solve():
n = ii()
cnt = 0
for i in range(-n, n+1):
if i == 0:
continue
for j in range(-n, n + 1):
mn = i + j - n
mx = i + j + n
if mn <= 1 <= mx:
cnt += 1
cnt += (2 * n + 1) ** 2 #
p(cnt)
if __name__ == "__main__":
tc = 1
for t in range(1, tc+1):
ret = solve()