# WA(?)

import sys, math
from itertools import permutations
input = sys.stdin.readline


n = int(input())

def check(p, a, b):
	return (p ** 2 < n * (p * a + b) + 1)

ans = 0
for a, b in permutations([*range(10)], 2):
	min_p = max(a, b) + 1
	if not(check(min_p, a, b)):
		continue
	left = min_p
	right = (n * a + math.sqrt((n * a) ** 2 + 4 * (n * b + 1))) / 2
	ans += int(right) - left + 1
print(ans)