  We discuss a very simple model of a 1-d disordered lattice, in which {\em
all} the electronic eigenstates are extended. The nature of these states is
examined from several viewpoints, and it is found that the eigenfunctions are
not Bloch functions although they extend throughout the chain. Some typical
wavefunctions are plotted. This problem originated in our earlier study of
extended states in the quasiperiodic copper-mean lattice [ Sil, Karmakar,
Moitra and Chakrabarti, Phys. Rev. B (1993) ]. In the present investigation
extended states are found to arise from a different kind of correlation than
that of the well-known dimer-type.
