his copy of Arithmetica, Pierre de Fermat had jotted the words I have a truly marvellous demonstration of this proposition which this margin is too narrow to contain.
The square had been converted to a cube, (x3 + y3 = z3), and mathematicians had spent centuries looking for the answer to Fermat's riddle. By the time Andrew Wiles solved the puzzle in the 1990s, he had been at it for ten years using the world's most advanced computer programme.
And all of a sudden she understood. The answer was so disarmingly simple. A game with numbers that lined up and then fell into place in a simple formula that was most similar to a rebus.
Fermat had no computer, of course, and Wiles' solution was based on mathematics that had not been invented when Fermat formulated his theorem. Fermat would never have been able to produce the proof that Wiles had presented. Fermat's solution was quite different.
She was so stunned that she had to sit down on a tree stump. She gazed straight ahead as she checked the equation.
So that's what he meant. No wonder mathematicians were tearing out their hair.
Then she giggled.
A philosopher would have had a better chance of solving this riddle.
She wished she could have known Fermat.
He was a cocky devil.
After a while she stood up and continued her approach through the trees. She kept the barn between her and the house.
CHAPTER 31
Thursday, April 7
Salander got into the barn through the outside hatch to an old manure drain. There were no livestock. She saw that the barn contained three cars - the white Volvo from Auto-Expert, an old Ford, and a somewhat newer Saab. Further in was a rusty harrow and other tools from the days when this had been a working farm.
She lingered in the darkness of the barn and watched the house. It was dusk and the lights were on in all the rooms on the ground floor. She couldn't see any movement, but she thought she saw the flickering glow of a television set. She glanced at her watch. 7:30. Time for Rapport.
She was surprised that Zalachenko would have chosen to live in such an isolated place. It was not like the man she remembered. She would never have expected to find him out in the country in a little white farmhouse. In some anonymous villa community, maybe, or in a vacation spot abroad. He must have made more enemies even than Salander herself. She was troubled that the place looked so undefended. But she had no doubt that he had weapons in the house.
After lingering for a long time, she slipped out of the barn into the twilight. She hurried across the yard, keeping her step light and her back to the facade of the house. Then she heard the faint sound of music. She walked noiselessly around the house and tried to peer through the windows, but they were too high.
Salander was instinctively uneasy. For the first half of her life she had lived in fear of the man inside that house. During the second half, ever since she had failed in her attempt to kill him, she had waited for the moment when he would come back into her life. This time she wasn't going to make any mistakes.
Zalachenko might be an old cripple, but he was a trained assassin who had survived on more than one field of battle. Besides, there was Ronald Niedermann to take into account. She would have much preferred to surprise Zalachenko outdoors, where he would be unprotected. She had no wish to talk to him and would have been satisfied with a rifle and a telescopic lens. But she had no rifle, and it was unlikely that he'd be taking an evening stroll. If she wanted to wait for a better opportunity, she would have to withdraw and spend the night in the woods. She had no sleeping bag, and even though the evening was mild, the night would be cold. Now that she had him within reach, she didn't want to risk letting him slip away again. She thought about Miriam Wu and about her mother.
She would have to get inside the house, but that was the worst possible scenario. Sure, she could knock on the door and fire her gun as soon as the door opened, and then go in to find the other bastard. But whoever was left would be alerted, and he would probably be armed. Time for a risk assessment. What were