The two big web search announcements of the year were the launch of WolframAlpha by Wolfram Research in mid-May and Microsoft's Bing a couple of weeks later.

Last week the two - which, like every other search technology, live in the shadow of Google - moved together a little for comfort.

Bing has done a deal to use WolframAlpha to answer queries relating to health, nutrition and advanced mathematics. For example, if you type "2^2^2^2^2" (^ means "to the power of") into Bing, it's supposed to dash off to WolframAlpha and come back with the result.

That's the theory, anyway. When I tried it out on the day of the announcement last Thursday, it wasn't yet working. Worse, Bing gave me the wrong answer, 65,536 - the result you get if you raise 2 to the power of 16.

Typing the query directly into WolframAlpha, meanwhile, returns a rather larger number - beginning with 2, followed by 19,728 digits. WolframAlpha correctly understands the problem as 2 to the power of 65,536.

Confused? Me too - but it is a big number, and we're apparently in good company. According to Wolfram Research blogger Schoeller Porter, Microsoft chairman Bill Gates was a little incredulous when he saw the calculation done.

"What, is that right?" Gates is alleged to have said when WolframAlpha creator Stephen Wolfram gave him a demo of the "computational knowledge machine" in the lead-up to the deal. The famously brainy British Wolfram - who had a PhD by 20 - replied: "We do mathematics!"

Arithmetic is clearly more Gates' subject - he worked out that a tie-up with Wolfram Research would help Microsoft in its market-share fight with Google.

One of the first rules of battle with a dominant opponent is to pretend you're not competing in the same market. Microsoft's strategy is to refer to Bing as a "decision engine" rather than a search engine, even if that's exactly what it looks like.

WolframAlpha might give it some justification to the claim, however. It, too, looks like a search engine. But when a query is typed in, it attempts to interpret it in the context of "trillions of pieces of data" and "tens of thousands of algorithms" to deliver live output.

The algorithms are derived from Mathematica, a computation program Stephen Wolfram developed a couple of decades ago, and the data has been vetted and input by Wolfram Research staff. Popular Science magazine last week gave WolframAlpha its 2009 computing innovation gong. But compete Google and Microsoft certainly do. Whereas they - and No2 search engine Yahoo, with which Microsoft did a 10-year technology and revenue-sharing deal in July - make money by selling ads around search results, WolframAlpha aims to pay its way through licensing deals.

A spokesman for the US-based company, John Ekizian, wouldn't say what terms have been agreed with Microsoft. He made it clear, however, that it won't be an exclusive arrangement.