| nounsharedextR(cren, cext, ren), Πok(ext, cext, ren, cren), Πok(ext, aext, ren, aren), oinj(cext), oinj(aext), oinj(ext), sameshared(cren, aren, ren), frag(IOAut(Π(start, cstart), Π(step, cstep, ren, cren, ext, cext), Π(ext, cext, ren, cren)))(pcσ, pα), frag(IOAut(astart, astep, aext))(aσ, aα), cext !(πra(step, cstep, ren, cren, pcσ, pα)) = aext !(aα) ⊦ frag(IOAut(Π(start, astart), Π(step, astep, ren, aren, ext, aext), Π(ext, aext, ren, aren))) (repls(step, cstep, cren, ren, aren, cext, aext, pcσ, pα, aσ, aα), repla(step, cstep, cren, ren, aren, cext, aext, pcσ, pα, aσ, aα)) |