Can somebody plz help me out with the following question-

You have been given a number say n and you have to do this following operation- find the resultant number which is formed by appending binary number of the first n positive numbers.

suppose n=4

1 in binary is 1

2 in binary is 10

3 in binary is 11

so finally the number formed is 1 10 11 or 11011->27's binary representation therefore the resultant number is 27

sorry for my bad explanation of the question