Date: Erev Rosh Hashanah 5581
From: Rabbi Moshe Sofer
To: Unknown recipient
The Chasam Sofer examines why the Rosh Hashanah Musaf prayer says 'remember the Akeidah for his seed' rather than 'for the seed of Yaakov,' and whether Esav's descendants are included in 'seed of Yitzchak.'
Source: Shu"t Chasam Sofer OC §165