[GAP Forum] DESIGN 1.4 release

[Leonard Soicher]

Dear GAP-Forum,

I am pleased to announce the release of version 1.4 of the DESIGN
package for GAP.  The DESIGN package is for constructing, classifying,
partitioning and studying block designs.

DESIGN 1.4 is available from both
   http://designtheory.org/software/gap_design/  and
   http://www.gap-system.org/Packages/design.html .

If you have not already done so, I strongly recommend that you upgrade GAP
to version 4.4.12 and GRAPE to version 4.3, before installing DESIGN 1.4.

The main changes from DESIGN 1.3 to DESIGN 1.4 are:

- Improved and documented the main features of function
SemiLatinSquareDuals, which can be used to classify (n x n)/k semi-Latin
squares and SOMA(k,n)s with given properties and small n.

- Added the function AGPointFlatBlockDesign, and improved the efficiency
of function PGPointFlatBlockDesign.

- Made function TDesignLambdas faster, in particular in the case of
a point-transitive design, when that design's record includes a known
point-transitive subgroup of the design's automorphism group.

- Improved the (undocumented) function IsPossiblySBIBD so that
TDesignBlockMultiplicityBound now makes full use of the Bruck-Ryser-Chowla
Theorem.

- Improved the speed of functions TDesignBlockMultiplicityBound and
ResolvableTDesignBlockMultiplicityBound when the bounds are large.

Regards,
Leonard Soicher