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## #1 2010-02-07 11:01:31

John E. Franklin
Member
Registered: 2005-08-29
Posts: 3,588

### Chess Knight Add 3 Sub 3

If you know how a knight
moves in chess, you might
enjoy this little matrix I
just came up with that has
subtracting the number 3.

Last edited by John E. Franklin (2010-02-07 15:07:13)

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## #2 2010-02-08 06:11:29

bobbym
From: Bumpkinland
Registered: 2009-04-12
Posts: 93,923

### Re: Chess Knight Add 3 Sub 3

Hi John;

We only have one problem here. If you take the tour 1 - 8 - 5 - 2 - 9 ? Only works if we are using modular arithmetic.

In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

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## #3 2010-02-08 06:48:09

John E. Franklin
Member
Registered: 2005-08-29
Posts: 3,588

### Re: Chess Knight Add 3 Sub 3

Yes, I'm only looking at the last digit.
Like 1 - 8 = 11 - 8 = 3

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## #4 2010-02-09 09:36:41

John E. Franklin
Member
Registered: 2005-08-29
Posts: 3,588

### Re: Chess Knight Add 3 Sub 3

Last edited by John E. Franklin (2010-02-14 14:05:51)

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## #5 2010-02-14 13:59:51

John E. Franklin
Member
Registered: 2005-08-29
Posts: 3,588

### Re: Chess Knight Add 3 Sub 3

Here's something I kind of like for adding numbers together
in my head, or on paper if you come up with shortcut
drawings and dots...

By putting the zero and five at the
center points, some very
pairs of numbers together.
There are 55 adding problems we
remember as children, 36 that are
not trivial (without 1 or 0 in them).
Try them all on this for fun in
geometric groups such as diagonals,
poles, longest diagonals, doubles,
horizontal beams, 5 added to any number,
etc.

Last edited by John E. Franklin (2010-02-17 04:57:03)

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