What is the most frequently asked question in Washington these days?

A clue: It has nothing to do with the state of the economy, religion, politics, war and peace, sports or even sex. Much bigger than all of those! The question is obvious to anybody who lives here. It is, of course: Will government workers get the Friday following Christmas and New Year's off?

The White House is getting a steady stream of calls from civil servants calling to remind the president that Dec. 26 is a Friday as is Jan. 2. Point being both are the days after regularly scheduled holidays, and wouldn't it be nice if people could get a four-day weekend. Most callers say they make the suggestion in the interests of economy, arguing that Uncle Sam could save a bundle if he shut down the furnaces Wednesday evening and not have to run them until the following Monday morning.

A number of federal workers have called The Washington Post, and other places that are supposed to know such things, to confirm the rumor that Carter will give federal workers two extra days off. He may.He may not. There has been no decision. Several people have also called to ask about the Friday following Thanksgiving, which is this week. Forget it. If you want the day after Thanksgiving off you will have to take leave, or be sick.

There is a precedent for letting federal workers have an extra day off when Christmas and New Year's fall on a Tuesday or Thursday. There is also a precedent for not letting them have the extra time off. President Carter okayed the bonus holidays once before. So did former president Nixon and Kennedy. But there is nothing in the rule books that says a president has to do so, and there is nothing to the rumor -- at least so far -- that President Carter has made a decision one way or the other. As an irked aide said yesterday: "He just lost the election. He has the problem of the hostages, the transition, what he's going to do next. I frankly doubt he has spent much time worrying about the subject."