  A lattice model of the directed self-avoiding walk is used to estimate the
possibility on the formation of an infinitely long linear semi-flexible
copolymer chain. The copolymer chain is assumed to composed of four different
types of the monomers. A method of the recursion relations is used to solve the
proposed model analytically to show that the probability of the formation of a
self-avoiding semi-flexible copolymer chain is independent of the stiffness of
the chain. It is a distinct result from our earlier study on the formation of a
Gaussian semi-flexible copolymer chain and the Gaussian chain is made up of
these four monomers, [P. K. Mishra, J. of Adv. Appl. Sci. Res. 2(4) 1-8
(2020)]. We have also calculated the average number of different types of the
bonding in the copolymer chain to show the distinctions in the behaviour of the
self-avoiding copolymer chain from the Gaussian polymer chain.
