“The Holocaust has become one of the most frequently invoked catalysts for composition in the 20th century–and now, beyond. It is also one of the most problematic. The risk of not doing justice to an event of such unbelievable horror must weigh like a heavy stone upon a composer’s mind…Those challenges were present in the “Remembrances: Reflections on the Holocaust” program from conductor Noreen Green and the Los Angeles Jewish Symphony at Encino’s Valley Beth Shalom on Sunday night – laudably ambitious in scope, serious in tone, but only variably winning in content. In some cases, the composers struck a nerve. Lucas Richman’s “Dachau Lied” expanded Herbert Zipper’s song “Arbeit Macht Frei” into a painfully sarcastic Weillian series of marches, with a narration (performed by his father, actor Peter Mark Richman) that followed the example of Schoenberg’s “A Survivor From Warsaw.”