How is an inheritance divided among a mother, a paternal grandfather (father's father), three full brothers, and a maternal half-brother?

If the heirs are limited to a mother, a grandfather, three full brothers, and one uterine brother, and the deceased left no other heirs, then the mother receives one-sixth due to the presence of a group of siblings. The grandfather receives one-third of the remainder because it is more beneficial for him. The remaining portion is divided equally among the full brothers. The uterine brother inherits nothing due to being excluded by the grandfather. Accordingly, the inheritance is divided into 54 shares: the mother receives nine shares, the grandfather fifteen shares, and each full brother ten shares. This is the opinion adopted in fatwas, stating that siblings inherit alongside the grandfather.

However, according to the view that the grandfather entirely excludes siblings, the inheritance is divided into six shares: the mother receives one share, and the remainder goes to the grandfather, with nothing for the siblings. Scholars have differed regarding the inheritance of siblings alongside the grandfather. Some believe that the grandfather excludes them, just like the father (such as the madhhab of Abu Hanifa), while others believe that they inherit with him (such as the madhhabs of Malik and Shafi'i).