Improved distance degree invariant of graphs

The Reverse distance degree invariant denoted by RDI is defined for a connected graph Λ asRDI(Λ)=∑r,s∈V(Λ)dgΛ(r)+dgΛ(s)distΛ(r,s).. The new graph invariant named improved reverse distance degree invariant is defined as I¯t(Λ)=∑r,s∈V(Λ)dgΛ(r)+dgΛ(s)distΛ(r,s)+t.. This paper is obtain the exact formulae for the improved reverse distance degree invariant and reverse distance degree invariant of corona product, rooted product, splice product and link product.