p—& gt； Q-—& gt；; R After calculation, it is found that m 1@m3@m4@m5@m7 @ stands for the symbol of absorbing or opening discrete mathematics.

And (p->; Q)-> (p—& gt； R) not (not p@q)@ (not p @ r)< =>；; (p is not q)@ (not p @ r)< =>；; (p not q) (not r@r))@ not p @ r

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