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#include <iostream>
#include <algorithm>
#include <stdio.h>
#include <set>
#include <vector>
#include <map>
using namespace std;

#define LL long long
#define MOD 1000000007LL

LL tab[300100];
/*
LL policz(LL p, LL l)
{
	LL r = 0;
	LL s = 0;
	if(l<=1)
	{
		if((tab[p]%MOD)%2==0) r = 1;
	}
	else
	{
		for(LL i=p+l-1;i>=p;i--)
		{
			s+=tab[i];
			s%=MOD;
			if (s%2==0)
			{
				printf("policz(%lld, %lld) :%lld\n",i,l-i,1LL);
				LL rc = policz(p,i-p);
				r+=rc;
				r%=MOD;
			}
		}
	}
	printf("policz(%lld, %lld) :%lld\n",p,l,r);
	return r;
}
*/

LL policzone[300100];

LL policz(LL l)
{
	LL r = 0;
	LL s = 0;
	if(l>=0 && policzone[l]>=0)return policzone[l];
	if(l<=1)
	{
		if((tab[0]%MOD)%2==0) r = 1;
	}
	else
	{
		for(LL i=l-1;i>=0;i--)
		{
			s+=tab[i];
			s%=MOD;
		}
		for(LL i=0;i<l;i++)
		{
			if (s%2==0)
			{
				//printf("policz(%lld, %lld) :%lld\n",i,l-i,1LL);
				LL rc = policz(i);
				r+=rc;
				r%=MOD;
			}
			s+=MOD;
			s-=tab[i];
			s%=MOD;
		}
	}
	//printf("policz(%lld, %lld) :%lld\n",0LL,l,r);
	policzone[l]=r;
	return r;
}

int main() {
	// your code goes here
	LL n;
	LL a;
	scanf("%lld",&n);
	policzone[0]=-1;
	for(int i=0;i<n;i++)
	{
		scanf("%lld",tab+i);
		policzone[i+1]=-1;
	}
	LL r = policz(n);
	printf("%lld",r);
	return 0;
}