数学 二进制 !!

来源:百度知道 编辑:UC知道 时间:2024/06/14 01:26:01
数学 二进制

Let k be a positive integer. Show that the number of powers of 2 that have k digits in decimal notation is at least three and at most four. Given that the largest power of 2 which is less than 10^2009 is 2^6673 , for how many k between 1 and 2009 inclusive, are there four powers of 2 that have k digits?

二进制的1011,转化为十进制
=1×2^0+1×2^1+0×2^2+1×2^3
=1+2+0+8
=11
1011从左到右,权依次是2的0次方,2的1次方,2的2次方,2的3次方。系数依次是1,1,0,1

个人翻译,希望没错:
令k为正整数,试证明:位数为k(十进制)且为2的整数幂的数最少有3个,最多有4个。若其中最大的2的整数幂小于10^2009 即2^6673 ,对于1和2009之间的k,有没有4个k位数的2的整数幂?

您这个题貌似不是二进制那么简单了,应该涉及数论的知识。当然,第二个问题,由于是有限数,可以用编程来解决。