# include "iostream"
# include "cstdio"

using namespace std;

long long K,A,B,Ans=1;

int main(){
	scanf("%lld%lld%lld",&K,&A,&B);
	if(B<=2 || A+2>=B) printf("%lld",K+1);
	else{
		Ans=A;
		K=K-A+1;
		Ans+=(K&1)+(K>>1)*(B-A);
		printf("%lld",Ans);
	}
	return 0;
}