#include <bits/stdc++.h>
using namespace std;
template <typename T>
inline bool chkmin(T &x, T y) {
  return y < x ? x = y, 1 : 0;
}
template <typename T>
inline bool chkmax(T &x, T y) {
  return x < y ? x = y, 1 : 0;
}
const int INF = 0x3f3f3f3f;
const int N = 20, mod = 1e9 + 7, Inv = (mod + 1) / 2;
char str[1 << N];
int A[1 << N];
inline int read() {
  int x = 0, flag = 1;
  char ch = getchar();
  while (!isdigit(ch) && ch != '-') ch = getchar();
  if (ch == '-') flag = -1, ch = getchar();
  while (isdigit(ch)) x = (x << 3) + (x << 1) + (ch - '0'), ch = getchar();
  return x * flag;
}
inline int Mod(int val) {
  if (val >= mod) val -= mod;
  if (val < 0) val += mod;
  return val;
}
inline void FWT(int P[], int len, int type) {
  for (int i = 2; i <= len; i <<= 1)
    for (int j = 0; j < len; j += i)
      for (int k = (0), kend = ((i >> 1) - 1); k <= kend; k++) {
        int x = P[j + k], y = P[j + k + (i >> 1)];
        if (type)
          P[j + k] = Mod(x + y), P[j + k + (i >> 1)] = Mod(x - y);
        else
          P[j + k] = 1ll * (x + y) * Inv % mod,
                P[j + k + (i >> 1)] = 1ll * Mod(x - y) * Inv % mod;
      }
}
int main() {
  int n = read(), ans = 0;
  scanf("%s", str);
  for (int i = (0), iend = ((1 << n) - 1); i <= iend; i++) A[i] = str[i] - '0';
  FWT(A, 1 << n, 1);
  for (int i = (0), iend = ((1 << n) - 1); i <= iend; i++)
    A[i] = 1ll * A[i] * A[i] % mod;
  FWT(A, 1 << n, 0);
  for (int i = (0), iend = ((1 << n) - 1); i <= iend; i++)
    ans = (ans + (1ll << (n - __builtin_popcount(i))) * A[i]) % mod;
  printf("%lld\n", ans * 3ll % mod);
  return 0;
}
