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Guest Message by DevFuse

I can't or I won't say

Best Answer bushindo, 17 October 2012 - 05:08 PM

My take on this

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#21 EventHorizon

EventHorizon

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Posted 22 October 2012 - 07:09 AM

Is there some other commonly accepted mathematical construct, e.g. denoted for set A by [A], that evaluates to a number, such that if A is a strict subset of B, then [A] < [B] even for infinite sets?

One more requirement for [A]: for finite sets, [A] = |A|

One more requirement:

If A is the real interval [0,1], and B = [0,0.5) U (0.5,1] U {2}
Then [A] = [B]

B is the same as A, except that 0.5 is removed, and 2 is added.
B is no longer a subset of A, but from an intuitive perspective should have the same "quantity of points".

Spoiler for To conserve space

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