2的n次方计算，支持大整数，nodejs代码

const fs = require('fs');
const log = content => {
    content && fs.appendFileSync('./out.txt', content + '\n', err => {});
};

let n = BigInt(1);

let s1, s2, s3
s1 = `${0}次方：`.padStart(6, ' ');
s2 = n.toString().padEnd(82, ' ');
s3 = `${n.toString().length}位数`;

log(s1 + s2 + s3);
for(let i = 0; i < 256; i++){
    n += n;

    s1 = `${i+1}次方：`.padStart(6, ' ');
    s2 = n.toString().padEnd(82, ' ');
    s3 = `${n.toString().length}位数`;
    log(s1 + s2 + s3);
}