function main(input){
    var tmp = input.split(/\r\n|\r|\n/);
    var N = Number(tmp[0]);
    var K = Number(tmp[1]);

    var res = 1;
    var tmp2;
    for(var i=0; i<N; i++){
        tmp2 = res*2;
        res += K;
        if(tmp2<res){
            res = tmp2;
        }
    }

    console.log(res);

}

main(require("fs").readFileSync("/dev/stdin", "utf8"));