At the party, people asked to snap a photo of the tattoo on his left forearm. Each time he pulled up his sleeve, David Wolnerman's unease faded further, as had the blurry blue numbers — 160344. For a long time, he didn't show the numbers that the Nazis put on his arm in 1940 at Auschwitz or tell what happened afterward. But he is 88, and he and his wife, Jennie, are the last known survivors of the Nazi concentration camps left in central Iowa. He wants people to see it now, including the 12-year-old girl from West Des Moines who wrote about his experiences in "A Lucky Lie," a book written for students that was unveiled at the April 16 party in Waukee. The hidden meaning behind that number, he told young author Sydney Pearl, came to him only later in life. Add the individual numbers together and they equal 18. Wolnerman had lied when he stood in line in 1940. Josef Mengele, the Nazi nicknamed "The Angel of Death," stood before him with a stick, pointing it to a line to the left or right as each person approached him. Wolnerman, then 13, noticed that the old, young and sickly were in a line to the left. When Mengele asked his age, Wolnerman said, "I am 18." Mengele pointed his stick to the right. The left line was eventually sent to the gas chambers.