If you have trouble getting any of these email me:
ralph@math.hawaii.edu.
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Partitions Algorithms. This is a 3 page note
describing efficient algorithms for calculations in partition
lattices. But this is superseded by my preprint
Computing congruences efficiently on my
papers page.
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Dean's Problem. This is an old lost problem in the theory of
free lattices. Only a partial solution is given.
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Unique factorization under direct product.
In their book Algebras, Lattices, Varieties, the authors ask
for a common generalization of the Birkhoff-Ore and Jonsson Theorems.
They point out
that if the hypothesis of Lemma 4 on page 270 could be
weakened to Con A finite dimensional,
then general theorem would be true.
The first paper shows that if there is no homomorphism from the 4 elements
in question onto M_4, then the strengthened Lemma 4 is true.
The other paper
gives an example showing the desired strengthening of Lemma 4 is false. But
it is not a counter-example to the general result.
Moreover, there is a different conjectured extension of Lemma 4, which also
would imply the desired common generalization of the Birkhoff-Ore and
Jonsson theorems, that is still open. So this approach to the problem
is still viable.
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Lectures on Projective Planes.
Some basics followed by a study of Hanna Neumann's embedding
of the Fano Plane into Hall Planes. This is motivated by the
question: are these subplanes maximal? If not what are the
intermediate planes?