# 愚直解

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

n = int(input())

ans = 0
for a, b in permutations([*range(10)], 2):
	min_p = max(a, b) + 1
	if(min_p ** 2 >= n * (min_p * a + b) + 1):
		continue
	p = min_p
	while(p ** 2 < n * (p * a + b) + 1):
		p += 1
	ans += p - min_p

print(ans)