CREATE TABLE table_31434 ("Series #" FLOAT, "Title" TEXT, "Directed by" TEXT, "Written by" TEXT, "Original air date" TEXT, "Viewers  ( million ) " TEXT)

How many people wrote the episode directed by Arvin Brown?
SELECT COUNT("Written by") FROM table_31434 WHERE "Directed by" = 'Arvin Brown'
SELECT COUNT("Written by") FROM "table_31434" WHERE "Directed by" = 'Arvin Brown'