Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| No. in series | No. in season | Title | Directed by | Written by | Original air date | Production code |
| --- | --- | --- | --- | --- | --- | --- |
| 40a | 1a | "Battle of the Century" | Norton Virgien | Mark Steen & Peter Hixson | September13,1997 | 401a |
| 40b | 1b | "A Perfect World" | Jim Duffy | Mark Palmer | September13,1997 | 401b |
| 41a | 2a | "The Lips Have It" | Bob Hathcock & Sergie Svislotski | Michael Price & Peter Hickson | September20,1997 | 402a |
| 41b | 2b | "Escape Claws" | Igor Kovalyov | Kat Likkel | September20,1997 | 402b |
| 42a | 3a | "Walk Like a Man" | Rick Bugental | Michael Price | September27,1997 | 403a |
| 42b | 3b | "A Friend in Need" | Jim Duffy | Mark Palmer | September27,1997 | 403b |
| 43a | 4a | "Watch the Watch" | Jeff McGrath | Michael Price | October4,1997 | 404a |
| 43b | 4b | "She Likes Me?" | Rick Bugental | Victor Wilson | October4,1997 | 404b |
| 44a | 5a | "Oblina Without a Cause" | Anthony Bell | Kat Likkel & Denise Downer | October11,1997 | 405a |
| 44b | 5b | "Slick Ick" | Andrei Svislotski & Bob Hathcock | David Regal & Mark Steen | October11,1997 | 405b |
| 45a | 6a | "Nuclear and Present Danger" | Rick Bugental | Ron Nelson & Kat Likkel | October18,1997 | 406a |
| 45b | 6b | "Loch Ness Mess" | Jim Duffy | Bill Braunstein | October18,1997 | 406b |
| 46a | 7a | "Super Ickis" | Jeff McGrath | Michael Price & Mitch Watson | October25,1997 | 407a |
| 46b | 7b | "The Substitute" | Jim Duffy | Mark Palmer | October25,1997 | 407b |
| 47a | 8a | "The Great Escape" | Zhenia Delioussine & Bob Hathcock | Bill Braunstein | November1,1997 | 408a |
| 47b | 8b | "Beast With Four Eyes" | Anthony Bell | David Regal | November1,1997 | 408b |
| 48a | 9a | "Side By Side" | Jeff McGrath | Kat Likkel | November8,1997 | 409a |
| 48b | 9b | "Hooked On Phobics" | Rick Bugental | Steve Skrovan | November8,1997 | 409b |
| 49a | 10a | "Spy vs. Monster" | Jim Duffy | Michael Price | November15,1997 | 410a |
| 49b | 10b | "Misery Date" | Jim Duffy | Mark Palmer | November15,1997 | 410b |
| 50a | 11a | "Clockwise" | Rick Bugental | Michael Price | November22,1997 | 411a |
| 50b | 11b | "Gromble Soup" | Anthony Bell | Denise Downer | November22,1997 | 411b |
| 51a | 12a | "Showdown" | Jim Duffy | Mark Palmer | November29,1997 | 412a |
| 51b | 12b | "Internal Affairs" | Jeff McGrath | Kat Likkel | November29,1997 | 412b |
| 52a | 13a | "Laugh Krumm Laugh" | Jim Duffy | Michael Price | December6,1997 | 413a |
Question:
What is the production code for the episode written by Kat Likkel & Denise Downer?
Answer:
405a