#include<cstdio>
#include<iostream>
#include<map>
#include<string>
#include<algorithm>
using namespace std;
#define i64 long long int
char s[99];int n;
map<pair<string,string>,int> Map;
int main(){
	scanf("%d%s",&n,s);
	for(int mask=0; mask<(1<<n); mask++){
		string r = "", b = "";
		for(int i=0; i<n; i++)if(mask&(1<<i))
			r += s[i];
		else
			b += s[i];
		reverse(b.begin(), b.end());
		Map[make_pair(r,b)]++;
	}
	i64 res = 0;
	for(int mask=0; mask<(1<<n); mask++){
		string r = "", b = "";
		for(int i=0; i<n; i++)if(mask&(1<<i))
			r += s[i+n];
		else
			b += s[i+n];
		reverse(b.begin(), b.end());
		auto tmp = make_pair(b,r);
		if(Map.count(tmp))
			res += Map[tmp];
	}
	cout << res << endl;
	return 0;
}
