Signed star image-subdomination numbers in graphs

Let image be a simple graph without isolated vertex with vertex set image and edge set image. A function image is said to be a signed star image-subdominating function of image if image for at least image vertices image of image, where image. The value image, taking over all signed star image-subdominating function image of image is called the signed star image-subdomination number of image and denoted by image. In this paper we give some bounds on the signed star image-subdomination number of graphs.