# 愚直解

import sys
input = sys.stdin.readline

l, r, m = map(int, input().split())
ans = 0
for n in range(l, r + 1):
	a = 1
	for i in range(1, n + 1):
		a *= i ** 2
	b = 0
	for i in range(1, n):
		c = 1
		for j in range(1, i + 1):
			c *= (n - j + 1) ** 2
		for j in range(i + 1, n + 1):
			c *= j ** 2
		b += c
	ans += b // a
	ans %= m
print(ans)