David Seff, a math professor at Brooklyn College, asked a female student to meet him in a classroom one late afternoon in August 2011 to help with a “listening experiment.” Alone with the young woman, Seff pounced on her, authorities charged.

Seff, now 68, allegedly grabbed her breasts and crotch. He pleaded guilty to misdemeanor harassment last September and was ordered to stay away from her for a year.

But his case never made the news — his name was kept under wraps by then-Brooklyn District Attorney Charles Hynes.

That secrecy is over, says DA Kenneth Thompson, who succeeded Hynes in January.

At The Post’s request, Thompson’s staff last week released 20 names of defendants in cases Hynes had refused to divulge because they involved Orthodox Jewish suspects and/or victims.

Hynes, who would issue press releases on non-Orthodox sex offenders, insisted he was shielding Orthodox victims or their families from Mafia-like intimidation in their insular community.

“We will treat all defendants and victims equally,” said Thompson’s chief-of-staff, Leroy Frazer. “We don’t have a policy for this particular group.”

Seff, an adjunct professor at Brooklyn College from 2003 to 2011, is now a part-time professor at Lehman College in The Bronx. CUNY officials had no comment. Seff did not return a call.

Other previously unpublicized suspects include:

Israel Moshe, 47, accused in 2010 of raping a 22-year-old woman with cerebral palsy who answered a Craigslist ad. He’s a fugitive with a warrant for arrest.

Alexander Rogalsky, 30, a camp counselor accused in 2011 of first-degree sodomy with a 13-year-old boy in 2003. Under a plea deal with Thompson in February, he copped to second-degree sodomy and got 10 years’ probation.

David Zimmer, 43, a locksmith convicted of sexually abusing a 10-year-old girl in 1999 and arrested again in 2012 for taking photos of a 9-year-old girl in Borough Park. He pleaded guilty to failure to register in June and faces sentencing Sept. 13.

Naftolis Schwartz, 57, a Hebrew teacher accused in 2012 of sexually abusing a 13-year-old student. He pleaded guilty in February to endangering the welfare of a child and received no jail time.

Yosef Ederi, 42, a repeat pedophile accused of sexually abusing a 12-year-old boy at their synagogue in 2011. He pleaded guilty to child endangerment in July 2013, was set free, and struck again. In May, he was convicted of molesting an 8-year-old boy and sentenced to a year in Rikers. He’s already out.

Criticized for going easy on rampant sex crimes in the Orthodox Jewish community, Hynes had launched an initiative in 2009 called Kol Tzedek, Hebrew for “voice of justice,” to encourage victims to come forward.

Kol Tzedek “no longer exists,” Frazer said.

Thompson has replaced Hynes’ Jewish-community liaison, Henna White, with Wolf Sender, a close ally of Democratic state Assemblyman Dov Hikind.

Chana Widawski, a social worker, is still on staff as a general victim advocate. An Orthodox hot line set up by Hynes remains, although calls are infrequent.