#include<bits/stdc++.h>
using namespace std;

typedef long long int       ll;
typedef unsigned long long int  ull;
typedef vector<int>         vi;
typedef vector<ll>          vll;
typedef vector<vi>          vvi;
typedef pair<int,int >      pii;
typedef vector< pii >       vpii;
typedef set<int>            sti;

#define sc                  scanf
#define pf                  printf
#define sci(n)              scanf("%d",&n)
#define scl(n)              scanf("%lld",&n)
#define scf(n)              scanf("%lf",&n)
#define scs(s)              scanf("%s",s)
#define pfi(n)              printf("%d",n)
#define pfl(n)              printf("%lld",n)
#define pff(n)              cout<<n
#define line                printf("\n")
#define spc                 printf(" ")
#define loop(i,x,y)         for(int i=int(x); i<=int(y); i++)
#define rloop(i,y,x)        for(int i=int(y); i>=int(x); i--)
#define cspf(i)             printf("Case %d: ", i)
#define pb                  push_back
#define mp                  make_pair
#define ff                  first
#define ss                  second
#define all(v)              v.begin(),v.end()
#define rall(v)             v.rbegin(),v.rend()
#define read()              freopen("input.txt", "r", stdin)
#define write()             freopen("output.txt", "w", stdout)
/// Constants
#define eps                 1e-9
#define PI                  acos(-1.0)  // 3.1415926535897932

int n;
int a[1009],x[1009];
bool check(int k)
{
    loop(i,1,k){
        x[i-1]=a[i]-a[i-1];
    }
    loop(i,1,n){
        int c=x[(i-1)%k]+a[i-1];
        if(c!=a[i]) return false;
    }
    return true;
}

int main()
{
    sci(n);
    loop(i,1,n) sci(a[i]);
    vi v;
    a[0]=0;
    for(int i=1;i<=n;i++){
        if(check(i))
            v.pb(i);
    }
    int sz=v.size();
    pfi(sz);line;
    loop(i,0,sz-1){
        pfi(v[i]);
        if(i+1<sz)
            spc;
    }
    line;
    return 0;
}