*. Tz and . Fi, and arcs connecting these places to transitions belonging to T21,r1U Tz*-r. It is worth noticing that the transitions belonging to fi are isolated nodes in CJ". Clearl-'* G(fr + 1) is obtained from Go and G(È) by merging transitions belonging to Tzr-r U?r and G'(k+ 1) is obtained from Go and G'(k) by merging transitions belongin g to T2p-1U ?r. According to propertv 8.6, G(k + 1) and G'(k + 1) have the same generating family of reduced T-invariants with respect to their input and output transitions ?

. Frc, 17 -G'(4) and G-(4) uith. Sa: {tt,t2} STEP 2: Elimina,be the closs-layer connecbions by iltrto4ucing new places and new transitions

. Appl, * algorithm B.l to obtain the set of minimal suppolt T-invariants of C

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