Given an integer N, the task is to check if it is a star number or not.
Star number is a centered figurate number that represents a centered hexagram (six-pointed star) similar to Chinese checker game. The first few Star numbers are 1, 13, 37, 73 …
Input: N = 13
Second star number is 13.
Second star number is 13, where as 37 is third.
Therefore, 14 is not a star number.
- The Kth term of the star number is given as
- As we have to check that the given number can be expressed as a star number or not. This can be checked as follows –
- Finally, check the value of computed using this formulae is an integer, which means that N is a star number.
Below is the implementation of the above approach:
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