Re: square number puzzle

On 10 Apr, 04:16, Ted Schuerzinger <fe...@xxxxxxxxxxxx> wrote:
On Wed, 09 Apr 2008 13:58:27 -0700, dgates wrote:
On Wed, 9 Apr 2008 13:26:57 -0700 (PDT), frank
<frankpo...@xxxxxxxxxxxxxxxxxx> wrote:

I think this is original (I made it up), but if someone has seen it
before can they let me know.

Start with a square number called x.

Subtract 15 from x to give another square number.

Add 15 to x to give a third square number.

All numbers and roots are positive integers and base10.

What are the three square numbers

Frank Potts

www.pottypuzzles.co.uk

It doesn't seem solvable.

Once you get higher than 7x7=49, the squares are too far apart for any
two of them to be 15 apart.

That seems to just leave 1 & 16, and 49 & 64 as the only square
integers that are 15 apart.

I think it shows up in Kordemsky's "Moscow Puzzles", but there's a
similar puzzle allegedly solved by Fibonacci: give a number that is a
perfect square, which yields a perfect square when 5 is added to it, and
which also yields a perfect square when 5 is subtracted from it.

(The answer isn't an integer, but there *is* a valid answer.)

--
Ted S
fedya at bestweb dot net
Now blogging athttp://justacineast.blogspot.com- Hide quoted text -

- Show quoted text -

This was the inspiration for the puzzle. I wanted something a bit more
lateral.

Frank
.

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