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Re: completeness of the relational lattice

From: Vadim Tropashko <vadimtro_invalid_at_yahoo.com>
Date: Tue, 26 Jun 2007 13:29:29 -0700
Message-ID: <1182889769.669708.83700@i38g2000prf.googlegroups.com>


On Jun 26, 10:55 am, Vadim Tropashko <vadimtro_inva..._at_yahoo.com> wrote:
> 13b: S /\ 00 = S and H /\ 00 = H and S \/ H != 00 and S /\ H = H'
> imply
> ((R /\ <S \/ 1E>) \/ H) /\ <S \/ 1E> = (R /\ <S \/ 1E>) \/ H'

Hmm, the S \/ H != 00 condition doesn't seem to be required. So rewritten a little the axiom

S /\ 00 = S and H /\ 00 = H imply

((R /\ <S \/ 1E>) \/ H) /\ <S \/ 1E> = (R /\ <S \/ 1E>) \/ (H /\ <S \/ 1E>)

looks like some kind of modularity law... Received on Tue Jun 26 2007 - 15:29:29 CDT

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