C++ :

#include<cstdio>
#include<cctype>
#include<cstring>
#include<iostream>
#include<cmath>
#define For1( i, a, b ) for( int i = a; i <= b; i++ )
#define For2( i, a, b ) for( int i = a; i >= b; i-- )
using namespace std;

int f[20] = { 1, 1, 1, 1, 1 };
int main()
{
    //freopen("in.txt", "r", stdin);
    For1( i, 5, 25 ) f[i] = f[i - 1] + f[i - 4];
    printf( "%d\n", f[25] );
    return 0;
}