Derrick Niederman

Derrick Niederman is a math professor at the College of Charleston. He makes crossword puzzles and he plays squash. His favorite number is 12.

Provided

Derrick Niederman teaches math at the College of Charleston with a twinkle in his eye. He tries, and often succeeds, to make it interesting for students.

In his spare time he plays squash.

And he makes crossword puzzles.

Niederman has been making puzzles, off and on, for 35 years. His latest, called “Mirror Reflections,” is the Sunday New York Times crossword puzzle that appears today in The Post and Courier. It’s the 20th puzzle he’s made for the Times, and the seventh during the Will Shortz era. The first one, a cryptic puzzle, appeared in January 1981.

The new one is complicated.

“I’ve been working on it, or one of its forerunners, for several years,” Niederman said. “It was a difficult construction. … Crossword construction is all about maintaining degrees of freedom. For this particular theme I lost a lot of freedom before I even began.”

He was necessarily cryptic about his cryptics, not wanting to give away too much before crossword enthusiasts had a chance to struggle with “Mirror Reflections.” Suffice it to say that the title is a hint.

Niederman earned his doctorate in mathematics at the Massachusetts Institute of Technology. He hadn’t made many puzzles back then, but he did enjoy puzzling over certain ideas.

“When I was at MIT, department chair Michael Artin posed the question, ‘Is it possible to construct a crossword puzzle with two independent solutions?’ I took it to heart.”

Before long, he was trying his hand at constructing crosswords.

“I wasn’t making very good progress on my thesis,” he said. “So I thought, why don’t I take some time off to prove that I can do something?”

His first three submissions to the Times were rejected. But Shortz’s predecessor, Eugene Maleska, recognized talent when he saw it. The fourth try was the charm. It ran in the Times a couple weeks after Niederman’s thesis defense. A reward of sorts.

Years later, he made a couple of small-format puzzles inspired by Artin’s rhetorical question. They worked, but Shortz felt they were too difficult to solve. A good mathematician, though, is nothing if not persistent.

The Times’ Sunday puzzles must have a theme, so when Niederman occasionally thinks of a good one, he’ll pitch it. The 2-for-1 puzzle, for instance, which has two correct answers for each question. Virginia battle sites? Yorktown, Manassas (both with eight letters). Dustin Hoffman movies? “Tootsie,” “Rainman” (both with seven letters).

Another idea was to construct a puzzle using the names of people whose initials matched the abbreviation of their home state: Stephen Colbert (SC), Louis Armstrong (LA), etc. It didn’t get published, alas. Too easy probably.

Another idea was a rebus puzzle that mimicked a chess game, with two 8x8 grids and a blend of letters and images. Imagine “Hal Holbrook” presented as HALHOLB + the picture of a rook, or “Marquee Names” presented as MAR + the image of a queen + AMES. Makes the head spin, doesn’t it?

“That one did get published, to considerable acclaim,” Niederman said. “What you have to be is persistent. You have to do everything you can to maintain your degrees of freedom, and you have to look at everything,” and look at everything repeatedly. Patience and persistence often leads to breakthroughs.

All crosswords are symmetrical, of course, and this presents certain challenges to the maker.

“I’m sure I’ve never made a perfect crossword, but I’ve come close,” he said. “Words weren’t made to intersect the way they do in a crossword.”

Niederman liked puzzle-making to another activity involving patterns, persistence and patience.

“Making a crossword puzzle is like knitting a sweater, except at any given point, no matter how close you are to the end, you might have to take the needles out and pull way back, all the way back to the waistband,” he said.

He ended up discarding 60 percent of “Mirror Reflections” and starting afresh. No wonder it took so many years.

“This puzzle, I can’t tell you how many times it was saved by a third or a fourth look.”

Contact Adam Parker at aparker@postandcourier.com or 843-937-5902.