题目

The elephant was lying heavily on its side, fast asleep. A few dogs started barking at it. The elephant woke up in a terrible anger: it chased the dogs into the village where they ran for safety.That didn't stop the elephant. It destroyed a dozen houses and injured several people. The villagers were scared and angry. Then someone suggested calling Parbati, the elephant princess.    Parbati Barua's father was a hunter of tigers and an elephant tamer. He taught Parbati to ride an elephant before she could even walk. He also taught her the dangerous art of the elephant round-up -- how to catch 下列图案由边长相等的黑，白两色正方形按一定规律拼接而成，设第个图案中白色小正方形的个数为.（1）第2个图案中有______个白色的小正方形；第3个图案中有______个白色的小正方形；与之间的函数表达式为______（直接写出结果）.（2）是否存在这样的图案，使白色小正方形的个数为2019个？如果存在，请指出是第几个图案；如果不存在，说明理由.