Saturday, 28 March 2015

Blog Post #61 - Five digit Number fun

Sunday musings!

Find this five digit number - ABCDE (Digits can repeat and not necessarily distinct)

- It can be expressed as (a ^ b) x (c ^ b) where a, b, c are integers
- (b ^ a) x (b ^ c) is a special number in its own sense
- Remove the 2nd digit (B) and it is a perfect square
- Add 1 to B and swap with A - (BACDE) and it is still a perfect square!

1 comment:

  1. Answer to Blog #61 - Five Digit Number fun

    The answer is 50625

    50625 = 3 ^ 4 x 5 ^ 4
    4 ^ 3 x 4 ^ 5 = 65536 which is a well known number in IT Parlance

    Remove 0 and it is a perfect square

    Add 1 to 0 and swap with 5 and you get 15625 which is a perfect square

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