The request from the president was straightforward: a comprehensive report on the outlook for the nation's energy supplies for the rest of the century.

But time was short. The Department of Energy had to gather the information, analyze it and publish the report in six months.

To do the job, the department leased 16 Apple Macintosh computers, support equipment and software. When the 350-page "Energy Security" report came out in March, it included charts, graphs and maps produced by the Macintosh. The report even had been typeset on the Macintosh, in an impressive demonstration of the computer's "desk-top publishing" capabilities.

According to DOE spokesman Phil Keif, the department chose the Macintosh because of its ability to quickly manipulate information and produce print-quality graphics. "At the time, that was the only thing available that could do the job," he said. "They {report writers} all think it worked very well."

For Apple Computer Inc.'s government sales staff in Reston, the DOE report was a small but significant victory.

The DOE's 16 Macintoshes represented a toehold in the company's fledgling efforts to get the federal government to use Apple computers. Although Apple is one of the biggest names in the personal computer business, it had not made a concerted attempt to sell computers to the federal government until recently, when it stepped up its efforts as part of its overall strategy to increase sales to business and office markets.

"It's not often that you have a major company in a technology area that has never sold to the government before," conceded Frank Sauer, Apple's national manager of government marketing and sales. "When we first came into government, the first reaction everybody had was, 'Aren't you a little bit late?' "

But Apple thinks its timing is perfect. The company has come to Washington at a time when many experts believe the government computer business is about to undergo a major change.

As federal agencies move to replace the first generation of personal computers they bought several years ago, their choice of machines is more varied than ever. And the future of computers using the popular MS-DOS operating system, such as those made by International Business Machines Corp., has been thrown into question by IBM's announcement earlier this year of a new line of personal computers using a different, still-under-development, operating system.

That has many experts predicting that MS-DOS is about to give way to another, yet-to-be-determined standard. Apple is vying with IBM's new system to become that standard.

"I believe that IBM had been a standards setter, and I do see a window, an opportunity to have that changed," said Shirley Prutch, vice president of information systems for Martin Marietta Corp.'s data systems division, which buys small computers from a variety of vendors for assembly into systems that are sold to the government. "People are reluctant -- they're saying, '{IBM} set the standards; what's going to happen next?' "

"The whole work station environment is really up for grabs the next couple of years," said Roger Cooper, a deputy assistant secretary of the Treasury with responsibilities for computer procurement. "I think it's going to be an interesting year or two; I'd call it life after the {IBM PC} AT and AT clones."

Apple's push to put Macintoshes on government desks provides a glimpse of how a company goes about getting a piece of the government-contracting pie.

To achieve its aim, the Cupertino, Calif.-based company has had to create a Washington sales staff from scratch and undertake what amounts to a full-fledged lobbying effort to persuade potential federal government customers of the value of the Macintosh. The company also has engaged in more traditional lobbying efforts, using its new Washington base to bring from Silicon Valley its argument that tariffs on Japanese semiconductors should be designed to do minimal damage to American companies -- a position similar to that eventually adopted by the Reagan administration.

Apple opened the Reston office last November, hiring experts in federal contracting from other companies and the government itself. Their mission: To market the Macintosh to the government as an alternative to the IBM-compatible MS-DOS personal computers models that dominate most federal microcomputer purchases. The company has brought countless government officials to its Reston offices to demonstrate the Macintosh and has gone into virtually every government agency trying to make its pitch.

Apple is touting the Macintosh as being easier and cheaper to learn and use than competing computers -- a big plus in the post-Gramm-Rudman world -- and for its capacity for complex graphic and desktop-publishing work.

So far, it's been a slow, uphill climb, with most of the company's sales to government agencies on the small scale of the DOE lease. But Apple recently won a contract to supply 1,000 Macintoshes to the Navy. And company officials believe that the Mac's newly expanded ability to communicate with other computers and to use MS-DOS programs written for IBM-compatible machines will increase the company's penetration of the government market.

In a way, Apple has been dealing indirectly with the government almost since the company's founding 10 years ago. Part of Apple's success has been built on pushing Apple computers into school systems, where the Apple II is by far the dominant educational computer. "What we hadn't done was to learn how to expand that knowledge of selling to education to sell to other parts of the government," Apple Chairman John Sculley said.

Apple identified the government market as a potential gold mine following the company's reorganization in May 1985, when Sculley ousted cofounder Steve Jobs and set Apple on a course for business and office customers -- including those in government.

Apple believed that the same changes in its product line that have made it successful in the business market would give it entre to the government market -- including more powerful versions of the Macintosh, such as the recently introduced Macintosh II, that are better able to connect with and be compatible to other brands of computers, particularly those using MS-DOS and the other major operating standard, Unix.

"We made a bet back in, I guess, late 1985 that we were going to have the right kinds of products for the government," Sculley said. "The problem is, we didn't know anything about selling to the government."

Sauer, a former Xerox Corp. government marketing executive who had been Apple's chief proponent of government sales, was assigned to put together a strategy for attacking the federal market. His plan, based in part on a correct hunch that IBM's new generation of computers would drop MS-DOS, called for hiring experienced Washington operatives rather than transferring Apple sales people east.

"We looked for people who had the skill sets we wanted, but relative to the government, not relative to Apple," he said. "We figured it was easier to teach them Apple than it was to teach them the government."

So Apple raided other companies and the government for talent. For example, Sauer's deputy, Ron Oklewicz, manager of federal government operations, came to Apple from Xerox by way of a small Northern Virginia high-technology company; James Johnson, Apple's director of government affairs, held a similar title at Xerox, and Bill Poulos, Apple's manager of government affairs, had been dealing with Congress on behalf of the Pentagon before retiring from the military last year to work for Apple.

In all, Apple now has 50 people working on government sales and marketing -- 30 of them in Reston, the rest in California. All but a handful came from outside the company.

It's not that it is that hard to do business with the federal government, Sauer said, "It's just different." Rather than selling directly to decision makers, as in the corporate world, government vendors must wade patiently through the government procurement process. "What that does is, it makes the sale more complex, and it makes the sale longer," Sauer said. "It takes a unique group of people to have the patience to deal with that . . . . I've got people who've been through the mill for years."

Sauers' sales force also had to persuade government procurement officials that Apple's computers represented a real alternative to MS-DOS machines. "The primary problem we face is the de facto technical standard in the federal government, which says that the only thing they'll buy is an IBM PC-compatible computer with an MS-DOS operating system," Johnson said. "We don't even get invited to bid because of that standard."

Apple has doggedly been attacking such barriers, lobbying everywhere from Capitol Hill to the Pentagon to individual federal agencies in an effort to demonstrate that the Macintosh has superior features and, if need be, can be fully compatible with, and connectable to, MS-DOS machines.

As it does when selling to the corporate world, Apple stresses to government customers the Macintosh's graphics capabilities, compatibility with MS-DOS programs, power and speed. But the company also makes a big pitch about how easy it is to learn to use the Macintosh, which operates with simple graphics-based commands rather than computerese. Apple claims that users can be trained on a Macintosh in days rather than the weeks it can take for MS-DOS machines.

Because training time and expenses are considered a hidden cost of computer purchases, Apple believes the simplicity of the Macintosh gives it a huge advantage over other machines when the full range of costs is taken into account. "It's great to buy a microcomputer for $750, but government would be prudent to look into what it would cost to make a person productive on that computer," Poulos said.

"Things like the ease of training become a major factor for the government when they look at total cost and realize that with Gramm-Rudman they can't add more people in the military or other government areas, and the last thing they want to do is to introduce computers and find out they have to put a whole infrastructure of support people there that are going to have to train people to use them," Sculley said. "So we've got a tremendous story with training."

Potential customers are listening. "A novice can get into it, use it easily, and not have to spend a lot of time learning it," Prutch said of the Macintosh. "When you retrain people, it takes time, and you also have that human factor involved that says, 'I don't want to use anything new.' But when it's easy to use, people get hooked on it."

And when people get hooked on it, they tend to get evangelical. Just as in the corporate world, where the Macintosh often got in the back door of companies by being adopted by a cult-like group of fans then spread throughout the firm, Apple is taking advantage of satisfied customers in government to spread the word.

A Macintosh users' group sprang up spontaneously at the Pentagon even though the Department of Defense wasn't officially using the machine, and many of the 7,000 members of the Washington-area Apple users' group are Mac owners who work in government. "Our best sales people are users," Poulos said.

"There is really a very large following of government Apple users, particularly Macintosh," Sauer said. "We call them champions, and they're all over the government." These Apple fans even have passed on tips on upcoming procurements so that the company knows when to bid. "People are excited that we're here . . . and they're asking us to help them get what they want," Poulos said.

Apple is taking the long view of its Washington venture -- the company is working on a five-year plan for government sales and does not expect to turn a profit on the operation until at least the third year. "We have an absolute commitment to be here as long as it takes to get the job done," Oklewicz said.

Ultimately, Apple would like government sales -- including state and local contracts, which it also is pursuing -- to account for 10 to 15 percent of its total sales, roughly similar to the industry average.

Contracts for handfuls of computers here and there won't do that. But Apple officials say the company is on the verge of being named as a supplier on several major procurements and in large team proposals and, Sculley said, "We've had a lot of interest with almost all the major departments of government with our products."