reserve k,n,n1,m,m1,m0,h,i,j for Nat,
  a,x,y,X,X1,X2,X3,X4,Y for set;
reserve L,L1,L2 for FinSequence;
reserve F,F1,G,G1,H for LTL-formula;
reserve W,W1,W2 for Subset of Subformulae H;
reserve v for LTL-formula;
reserve N,N1,N2,N10,N20,M for strict LTLnode over v;
reserve w for Element of Inf_seq(AtomicFamily);

theorem
  H in the LTLnew of N & (H is disjunctive or H is Until or H is Release
) implies (w |= *N iff (w |= *SuccNode1(H,N) or w |= *SuccNode2(H,N))) by Lm18
