n, k = map(int, input().split())
x = list(map(int, input().split()))
path = [0] * k
ans = 0
def dfs(depth):
if depth == k:
if sum(path) <= 1:
return
for i in range(2, sum(path) // 2):
if sum(path) % i == 0:
return
global ans
ans += 1
return
for i in range(n):
if path.count(x[i]) == 0:
path[depth] = x[i]
dfs(depth + 1)
dfs(0)
print(ans)