n, s = map(int, input().split())

def fact(n):
    return 1 if n <= 1 else n * fact(n - 1)

p = []
used = [False] * s
for i in range(s):
    for x in range(s):
        if used[x]:
            continue
        if n >= fact(s - 1 - i):
            n -= fact(s - 1 - i)
        else:
            p.append(x)
            used[x] = True
            break
q = [None] * s
for i in range(s):
    q[p[i]] = i

ans = 0
used = [False] * s
for i in range(s):
    for x in range(s):
        if used[x]:
            continue
        if x != q[i]:
            ans += fact(s - 1 - i)
        else:
            used[x] = True
            break
print(ans)