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Guest Message by DevFuse

# 401 unit diameter Circles in a 400 unit rectangle

15 replies to this topic

### #11 TimeSpaceLightForce

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Posted 15 July 2013 - 09:03 AM

Spoiler for

Spoiler for It has to be different in the following way

Spoiler for

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### #12 plasmid

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Posted 15 July 2013 - 02:12 PM

Spoiler for It looks possible

If you try to compact the top row like this, at some point during compaction the circles on the top row must lie directly above the circles on the bottom row at which point such compaction cannot continue. Or if you propose that the compaction traverses a zone where circle N-1 is just a tiny bit to the right of circle M-1 below it and circle N is just a tiny bit to the left of circle M below it, all without ever having the top row of circles exactly above the bottom row, then if the lower circles M-1 and M are touching then it would require you to somehow pack more efficiently in that block of four circles than rectangular packing.

Edit: although now that I understand TSLF's answer, I think that it should work in principle. Haven't verified the calculations myself yet though.

Edit2:

Spoiler for now that I did the calculations

Edited by plasmid, 15 July 2013 - 03:03 PM.

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Posted 26 November 2013 - 03:56 AM

Spoiler for the solution

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### #14 harey

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Posted 27 November 2013 - 12:09 AM

Really easy!!!

Spoiler for

Edited by harey, 27 November 2013 - 12:10 AM.

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Posted 27 November 2013 - 02:24 AM

I disagree with your first perverted twist of the rules harey.as i feel that the overlapping and unit circle (designated diameter) was implied from the previous sentence.

Edited by BMAD, 27 November 2013 - 02:25 AM.

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### #16 TimeSpaceLightForce

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Posted 28 November 2013 - 08:48 PM

Spoiler for the solution

Does these triads form an equilateral triangle?

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