#if defined(LOCAL) or not defined(LUOGU)
#pragma GCC optimize(3)
#pragma GCC optimize("Ofast,unroll-loops")
#endif
#include<bits/stdc++.h>
using namespace std;
struct time_helper
{
#ifdef LOCAL
	clock_t time_last;
#endif
	time_helper()
	{
#ifdef LOCAL
		time_last=clock();
#endif
	}
	void test()
	{
#ifdef LOCAL
		auto time_now=clock();
		std::cerr<<"time:"<<1.*(time_now-time_last)/CLOCKS_PER_SEC<<";all_time:"<<1.*time_now/CLOCKS_PER_SEC<<std::endl;
		time_last=time_now;
#endif
	}
	~time_helper()
	{
		test();
	}
}time_helper;
#ifdef LOCAL
#include"dbg.h"
#else
#define dbg(...) (__VA_ARGS__)
#endif
namespace Fread{const int SIZE=1<<16;char buf[SIZE],*S,*T;inline char getchar(){if(S==T){T=(S=buf)+fread(buf,1,SIZE,stdin);if(S==T)return'\n';}return *S++;}}namespace Fwrite{const int SIZE=1<<16;char buf[SIZE],*S=buf,*T=buf+SIZE;inline void flush(){fwrite(buf,1,S-buf,stdout);S=buf;}inline void putchar(char c){*S++=c;if(S==T)flush();}struct NTR{~NTR(){flush();}}ztr;}
#define getchar Fread::getchar
#define putchar Fwrite::putchar
#define Setprecision 10
#define between '\n'
#define __int128 long long
template<typename T>struct is_char{static constexpr bool value=(std::is_same<T,char>::value||std::is_same<T,signed char>::value||std::is_same<T,unsigned char>::value);};template<typename T>struct is_integral_ex{static constexpr bool value=(std::is_integral<T>::value||std::is_same<T,__int128>::value)&&!is_char<T>::value;};template<typename T>struct is_floating_point_ex{static constexpr bool value=std::is_floating_point<T>::value||std::is_same<T,__float128>::value;};namespace Fastio{struct Reader{template<typename T>typename std::enable_if_t<std::is_class<T>::value,Reader&>operator>>(T&x){for(auto &y:x)*this>>y;return *this;}template<typename T>typename std::enable_if_t<is_integral_ex<T>::value,Reader&>operator>>(T&x){char c=getchar();short f=1;while(c<'0'||c>'9'){if(c=='-')f*=-1;c=getchar();}x=0;while(c>='0'&&c<='9'){x=(x<<1)+(x<<3)+(c^48);c=getchar();}x*=f;return *this;}template<typename T>typename std::enable_if_t<is_floating_point_ex<T>::value,Reader&>operator>>(T&x){char c=getchar();short f=1,s=0;x=0;T t=0;while((c<'0'||c>'9')&&c!='.'){if(c=='-')f*=-1;c=getchar();}while(c>='0'&&c<='9'&&c!='.')x=x*10+(c^48),c=getchar();if(c=='.')c=getchar();else return x*=f,*this;while(c>='0'&&c<='9')t=t*10+(c^48),s++,c=getchar();while(s--)t/=10.0;x=(x+t)*f;return*this;}template<typename T>typename std::enable_if_t<is_char<T>::value,Reader&>operator>>(T&c){c=getchar();while(c=='\n'||c==' '||c=='\r')c=getchar();return *this;}Reader&operator>>(char*str){int len=0;char c=getchar();while(c=='\n'||c==' '||c=='\r')c=getchar();while(c!='\n'&&c!=' '&&c!='\r')str[len++]=c,c=getchar();str[len]='\0';return*this;}Reader&operator>>(std::string&str){str.clear();char c=getchar();while(c=='\n'||c==' '||c=='\r')c=getchar();while(c!='\n'&&c!=' '&&c!='\r')str.push_back(c),c=getchar();return*this;}Reader(){}}cin;const char endl='\n';struct Writer{typedef __int128 mxdouble;template<typename T>typename std::enable_if_t<std::is_class<T>::value,Writer&>operator<<(T x){for(auto &y:x)*this<<y<<between;*this<<'\n';return *this;}template<typename T>typename std::enable_if_t<is_integral_ex<T>::value,Writer&>operator<<(T x){if(x==0)return putchar('0'),*this;if(x<0)putchar('-'),x=-x;static int sta[45];int top=0;while(x)sta[++top]=x%10,x/=10;while(top)putchar(sta[top]+'0'),--top;return*this;}template<typename T>typename std::enable_if_t<is_floating_point_ex<T>::value,Writer&>operator<<(T x){if(x<0)putchar('-'),x=-x;x+=pow(10,-Setprecision)/2;mxdouble _=x;x-=(T)_;static int sta[45];int top=0;while(_)sta[++top]=_%10,_/=10;if(!top)putchar('0');while(top)putchar(sta[top]+'0'),--top;putchar('.');for(int i=0;i<Setprecision;i++)x*=10;_=x;while(_)sta[++top]=_%10,_/=10;for(int i=0;i<Setprecision-top;i++)putchar('0');while(top)putchar(sta[top]+'0'),--top;return*this;}template<typename T>typename std::enable_if_t<is_char<T>::value,Writer&>operator<<(T c){putchar(c);return*this;}Writer&operator<<(char*str){int cur=0;while(str[cur])putchar(str[cur++]);return *this;}Writer&operator<<(const char*str){int cur=0;while(str[cur])putchar(str[cur++]);return*this;}Writer&operator<<(std::string str){int st=0,ed=str.size();while(st<ed)putchar(str[st++]);return*this;}Writer(){}}cout;}
#define cin Fastio::cin
#define cout Fastio::cout
#define endl Fastio::endl

void solve();
main()
{
	int t=1;
	// cin>>t;
	while(t--)solve();
}
constexpr int p=1e9+7;
constexpr long long pt=1000000007998244353;
int b[300001],dp[300001];
long long pw2[2000001],sum[300001];
int st[2000001];
int tim=0;
void dc(int l,int r)
{
	if(l==r){dp[l]=(dp[l]+dp[l-1])%p;return;}
	int mi=(l+r)/2;
	dc(l,mi);
	vector<pair<int,int>>eg;
	{
		tim++;
		vector<pair<long long,int>>mpl,mpr;
		for(int x=mi;x>=l;x--)
		mpl.emplace_back(sum[x-1],x-1);
		int mx=0;
		for(int x=mi+1;x<=r;x++)
		{
			int v=b[x];
			while(st[v]==tim)st[v]=0,v++;
			st[v]=tim;
			mx=max(mx,v);
			long long val=(sum[x]-pw2[mx+1]+pt)%pt;
			mpr.emplace_back(val,x);
		}
		sort(mpl.begin(),mpl.end());
		sort(mpr.begin(),mpr.end());
		int l0=0,r0=0;
		while(l0!=mpl.size()&&r0!=mpr.size())
		{
			if(mpl[l0].first==mpr[r0].first){eg.emplace_back(mpl[l0].second,mpr[r0].second);r0++;}
			else if(mpl[l0].first<mpr[r0].first)l0++;
			else r0++;
		}
	}
	{
		tim++;
		vector<pair<long long,int>>mpl,mpr;
		for(int x=mi+1;x<=r;x++)
		mpr.emplace_back(sum[x],x);
		int mx=0;
		for(int x=mi;x>=l;x--)
		{
			int v=b[x];
			while(st[v]==tim)st[v]=0,v++;
			st[v]=tim;
			mx=max(mx,v);
			long long val=(sum[x-1]+pw2[mx+1])%pt;
			mpl.emplace_back(val,x-1);
		}
		sort(mpl.begin(),mpl.end());
		sort(mpr.begin(),mpr.end());
		int l0=0,r0=0;
		while(l0!=mpl.size()&&r0!=mpr.size())
		{
			if(mpl[l0].first==mpr[r0].first){eg.emplace_back(mpl[l0].second,mpr[r0].second);l0++;}
			else if(mpl[l0].first<mpr[r0].first)l0++;
			else r0++;
		}
	}
	sort(eg.begin(),eg.end());
	eg.erase(unique(eg.begin(),eg.end()),eg.end());
	// dbg(l,r,eg);
	for(auto _:eg)
	{
		int u=_.first,v=_.second;
		dp[v]=(dp[u]+dp[v])%p;
	}
	dc(mi+1,r);
}
void solve()
{
	int n;
	cin>>n;
	dp[0]=pw2[0]=1;
	for(int x=1;x<=2000000;x++)
	pw2[x]=2*pw2[x-1]%pt;
	for(int x=1;x<=n;x++)
	cin>>b[x],sum[x]=(sum[x-1]+pw2[b[x]])%pt;
	dc(1,n);
	cout<<dp[n]<<endl;
}