Write the cubes of 5 natural numbers which are of the form and verify the following:

“The cube of a natural number of the form 3n+1 is a natural number of the same from i.e. when divided by 3 it leaves the remainder 1’

First 5 natural numbers in the form of ( 3n + 1) are = 4 , 7 , 10 , 13 , 16


Cube of these numbers are,


= 43 = 4 × 4 × 4 = 64


= 73 = 7 × 7 × 7 = 343


= 103 = 10 × 10 × 10 = 1000


= 133 = 13 × 13 × 13 = 2197


= 163 = 16 × 16 × 16 = 4096


We find that all these cubes gives remainder 1 when divided by ‘3’


Hence, statement is true.


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