#include <stdio.h>
int a(int n){
int i;
int a[100];
a[0]=0;
a[1]=1;
for(i=2;i<=n;i++){
a[i]=5*a[i-1]+a[i-2];
}return a[n];
}
int main(void) {
// your code goes here
return 0;
}
I2luY2x1ZGUgPHN0ZGlvLmg+CmludCBhKGludCBuKXsKCWludCBpOwoJaW50IGFbMTAwXTsKCglhWzBdPTA7CglhWzFdPTE7Cglmb3IoaT0yO2k8PW47aSsrKXsKCQlhW2ldPTUqYVtpLTFdK2FbaS0yXTsKCX1yZXR1cm4gYVtuXTsKfQoKaW50IG1haW4odm9pZCkgewoJLy8geW91ciBjb2RlIGdvZXMgaGVyZQoJcHJpbnRmICgiJWQiLGEoNCkpOwoJcmV0dXJuIDA7Cn0K