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Distinct Digit Determination II (Posted on 2010-12-15)

Each of A and B is a (base 15) positive integer , with A containing precisely 201 digits and, B containing precisely 202 digits, where:

A = 77…..779 (the digit 7 is repeated precisely 200 times followed by 9), and: B= 77…..779 (the digit 7 is repeated precisely 201 times followed by 9)

Determine the distinct digits in the base 15 representation of A². What are the distinct digits in the base 15 representation of B²?

*** For an extra challenge, solve this puzzle without the help of a computer program.

Submitted by K Sengupta

Rating: 5.0000 (1 votes)

Solution: (Hide)

The distinct digits of A^2 are 3, B, 5 and 6; the distinct digits of B^2 are 3, B, C and 6.
For an explanation, refer to the solution submitted by Charlie in this location.

Comments: ( You must be logged in to post comments.)

Subject	Author	Date
Manual Approach (spoiler)	Steve Herman	2010-12-16 16:27:38
computer solution	Charlie	2010-12-15 19:07:19

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