(Part of an article by Karen W. Arenson in The New York Times.)

Every year on college campuses across the US and Canada, the most brilliant math students face the ultimate challenge. For six hours they, struggle with problems from the merely intractable to the seemingly impossible.

Every spring, five are choosen winners of the William Lowell Putnam Mathematical Competition. Every year for 56 years they have all been men. Until this year. This spring, Ioana Dumitriu, 20, a New York University sophomore from Romania, became the first woman to win the award.

The test that Ms. Dumitriu won is daunticaly difficult, even for math majors. About half of the 2,407 test takers score 2 or fewer out of the possible 120, and a third score 0. Some students walk out after staring at the questions. Ms. Dumitriu said that in the six hours allotted, she had time to do 8 of the maximum 12 problems, each worth a maximum of 10 points. The last one she did took her only 10 minutes. This year, Ms. Dumitriu and her five co-winners scored between 76 and 98. She does not know her exact score or rank because the organizers do not announce them.

"I didn't ever tell myself that I was unlikely to win, that no women before had ever won and therefore I couldn't, It is not that I forget that I am a woman. I just don't see it as as obstacle."