הַעֲנֵ֤יק תַּעֲנִיק֙ ל֔וֹ מִצֹּ֣אנְךָ֔ וּמִֽגָּרְנְךָ֖ וּמִיִּקְבֶ֑ךָ אֲשֶׁ֧ר בֵּרַכְךָ֛ יְהוָ֥ה אֱלֹהֶ֖יךָ תִּתֶּן־לֽוֹ׃
באַשענקען זאָלסטו אים באַשענקען פֿון דײַנע שאָף, און פֿון דײַן שײַער, און פֿון דײַן קעלטער; מיט װאָס ה׳ דײַן גאָט האָט דיך געבענטשט, דערפֿון זאָלסטו אים געבן.
Sefer HaMitzvot
That is that He commanded us to exclusively cut off the seed of Amalek - males, females, adults and children - from among the rest of the descendants of Esav. And that is His, may He be exalted, saying, "you shall blot out the memory of Amalek" (Deuteronomy 25:19). And we already mentioned (Sefer HaMitzvot, Positive Commandments 173), "Three commandments were commanded to Israel upon their entrance to the land: To appoint a king over them; to build the [Temple]; and to cut off the seed of Amalek." And this war is a commanded war. And the regulations of this commandment have already been explained in the Chapter 1 of Sotah. (See Ki Tetzei; Mishneh Torah, Kings and Wars 5.)