Avraham Yitzchak Bloch died in 1941.
Avraham Yitzchak Bloch was born in 1891.
Avraham (Abraham), Yitzchak (Isaac), and Yaakov (Jacob).
The three patriarchs are: Avraham, Yitzchak, and Ya'akov
Yitzchak is the son of Avraham. He was the child of the Promise between Hashem and Avraham, born to parents who were 90 and 100. Yitzchak is the sign of the covenant between THE ETERNAL and Avraham, spoken of in Bereshit 17. Go read it, it's awesome. Why is he cool? What other religion has covenants before Hashem for more than 4,000 years? What other nation has actual land promised to them by Hashem through ancestors who actually spoke to HIM? Besides, Yitzchak was the granddad of the whole nation, all twelve tribes. Pretty awesome if you ask me.
Yitzchak Blazer died in 1907.
Yitzchak Lowy died in 1942.
Levi Yitzchak Horowitz died in 2009.
Yosef Yitzchak Shloush died in 1960.
Levi Yitzchak Schneerson died in 1944.
Yitzchak Yaacov Reines died in 1915.
Shmuel Yitzchak Hillman died in 1953.
Avraham Stern died in 1942.