CREATE TABLE table_30377 ("No. in series" FLOAT, "No. in season" FLOAT, "Title" TEXT, "Directed by" TEXT, "Written by" TEXT, "Original air date" TEXT, "Production code" FLOAT)

What is the series number for the episode written by janet leahy?
SELECT MIN("No. in series") FROM table_30377 WHERE "Written by" = 'Janet Leahy'
SELECT MIN("No. in series") FROM "table_30377" WHERE "Written by" = 'Janet Leahy'