user: Question: Which Series is on April 18?
Columns: ['Game', 'Date', 'Opponent', 'Score', 'Series']
Types: ['real', 'text', 'text', 'text', 'text']
Sample row: [1.0, 'April 18', 'New York Islanders', '3–0', 'Flyers lead 1–0']
SQL:

assistant: SELECT "Series" FROM "Table" WHERE "Date" = 'April 18';