#include <bits/stdc++.h>
using namespace std;
#define paiu return
#define moment 0;
#define int long long
#define ll long long
#define forr(i,x) for (int i=0; i<x; i++)
#define forn(i,x) for (int i=0; i<x; i++)
#define forrr(i,j,x) for (int i=j; i<x; i++)
#define di(a,n) deque<int> a(n,0)
#define dll(a,n) deque<ll> a(n,0)
#define vi(a,n) vector<int> a(n,0)
#define vll(a,n) vector<ll> a(n,0)
//cringe define
#define vii(a,n) vi(a,n); forr(i,n) cin>>a[i];
vector<int> ___makeprefsum(vector<int>&a) {
int n=a.size();
vi(pr,n+1);
forn(i,n) pr[i+1]=pr[i]+a[i];
return pr;
}
#define prefsum(pr,a) vector<int> pr=___makeprefsum(a);
#define all(v) v.begin(),v.end()
#define rall(v) v.rbegin(),v.rend()
#define pb(x) push_back(x)
#define pf pop_front();
#define last(c) c[c.size()-1]
#define f first
#define s second
#define pi pair<int, int>
#define mp(x,y) make_pair(x, y)
const ll mod = 1000000007;
const double ppi = acos(0) * 2;
//const int maxn = 3e5+1;
const int inf = INT_MAX;
const ll linf = LLONG_MAX;
const ll mmod = 998244353;
vector<int> tow(1e6+5);
vector<int> dp(1e6+5);
void ini() {
tow[0]=0;
int sum=0;
for (int i=1; i<=1e6; i++) {
tow[i]=sum+1;
sum+=tow[i];
}
dp[0]=0;
for (int i=1; i<=1e6; i++) {
}
}
int pw2(int x, vector<int>&a) {
int ret=1;
for (int bit=32; bit>=0; bit--) {
if (x&(1ll<<bit)) { ret*=a[bit]; ret%=mod; }
}
return ret;
}
void solve() {
int n; cin>>n;
int k; cin>>k;
vector<int> binexp(1e6+3,2);
binexp[0]=2;
forn(i,1e6) binexp[i+1]=(binexp[i]*binexp[i])%mod;
int ans=1;
int lev=n-1;
while (lev>=0) {
if (k%2) {
k=(k+1)>>1;
} else {
ans+=pw2(lev,binexp);
//cout<<ans<<' ';
ans%=mod;
k=k>>1;
}
lev--;
}
cout<<ans;
}
int32_t main() {
ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
//init_primes();
int t=1;
//cin>>t;
while(t--) solve();
paiu moment
}
