The spectrum of optimal strong partially balanced designs with block size five Original Research Article

We shall refer to a strong partially balanced design image whose b is the maximum number of blocks in all image, as an optimal strong partially balanced design, briefly image. The author in paper (Discrete Math. 279 (2004) 173) investigated the existence of image and gave the spectra of image for image. In this article we shall investigate the existence of image and give the spectrum of image for the remaining case image.