import std.conv, std.functional, std.range, std.stdio, std.string;
import std.algorithm, std.array, std.bigint, std.bitmanip, std.complex, std.container, std.math, std.mathspecial, std.numeric, std.regex, std.typecons;
import core.bitop;

class EOFException : Throwable { this() { super("EOF"); } }
string[] tokens;
string readToken() { for (; tokens.empty; ) { if (stdin.eof) { throw new EOFException; } tokens = readln.split; } auto token = tokens.front; tokens.popFront; return token; }
int readInt() { return readToken.to!int; }
long readLong() { return readToken.to!long; }
real readReal() { return readToken.to!real; }

bool chmin(T)(ref T t, in T f) { if (t > f) { t = f; return true; } else { return false; } }
bool chmax(T)(ref T t, in T f) { if (t < f) { t = f; return true; } else { return false; } }

int binarySearch(alias pred, T)(in T[] as) { int lo = -1, hi = cast(int)(as.length); for (; lo + 1 < hi; ) { const mid = (lo + hi) >> 1; (unaryFun!pred(as[mid]) ? hi : lo) = mid; } return hi; }
int lowerBound(T)(in T[] as, T val) { return as.binarySearch!(a => (a >= val)); }
int upperBound(T)(in T[] as, T val) { return as.binarySearch!(a => (a > val)); }


debug {
enum L = 3;
} else {
enum L = 600;
}

void main() {
  const N = readInt;
  
  auto gs = new int[L + 2];
  foreach (i; 2 .. L + 2) if (i <= N) {
    writefln("? %s", i);
    stdout.flush;
    gs[i] = readInt;
  }
  
  foreach (x; 1 .. N + 1) {
    bool ok = true;
    foreach (i; 2 .. L + 2) if (i <= N) {
      ok = ok && (gs[i] == gcd(x, i));
    }
    if (ok) {
      writefln("! %s", x);
    }
  }
  stdout.flush;
}