theorem Th27: :: MODELC_3:27

for n being Nat
for L being FinSequence
for F, v being LTL-formula st L is_Finseq_for v & not F in the LTLold of (CastNode ((L . 1),v)) & 1 < n & n <= len L & F in the LTLold of (CastNode ((L . n),v)) holds
ex m being Nat st
( 1 <= m & m < n & not F in the LTLold of (CastNode ((L . m),v)) & F in the LTLold of (CastNode ((L . (m + 1)),v)) )