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Design parameters are 2-(7,3,3), b=21

Blocks of the design are:
012 012 012 034 034 034 056 056 056 135 135 135 146 146 146 236 236 236 245 245 245
The design is not simple, with support 7

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Auto’m group order is 168

All non-isomorphic minimal defining sets are:

012 012 012 034 034 034 135 135 135
Size=9 |Aut|=6

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Size Count
—- —–
9 1

Only 1 (non-isomorphic) minimal defining set
Totally 28 (inequivalent) minimal defining sets

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