import sys
readline=sys.stdin.readline

def Divisor_Counts(N):
    divisor_counts=[float('inf')]+[1]*N
    for p in range(2,N+1):
        if divisor_counts[p]!=1:
            continue
        pp=p
        e=1
        while pp<=N:
            for i in range(pp,N+1,pp):
                divisor_counts[i]+=divisor_counts[i]//e
            e+=1
            pp*=p
    return divisor_counts

N,p=readline().split()
N=int(N)
p=float(p)
ans=0
cnt=Divisor_Counts(N)
for n in range(2,N+1):
    ans+=(1-p)**(cnt[n]-2)
print(ans)