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Design parameters are 2-(9,3,1), b=12

Blocks of the design are:
012 036 048 057 138 147 156 237 246 258 345 678
The design is simple

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Auto’m group order is 432

All non-isomorphic minimal defining sets are:

012 036 048 138 147
Size=5 |Aut|=2
036 057 138 147
Size=4 |Aut|=8

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Size Count
—- —–
4 1
5 1

Only 2 (non-isomorphic) minimal defining sets
Totally 270 (inequivalent) minimal defining sets

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