1. Bob pointed to an invoice on his desk. "Do you see anything funny about that five-figure serial number?" he asked. "Let me try something," replied Andy, scribbling on a scrap of paper. "Yes, it happens to be a perfect square." "That's part of it," Bob told him. "If you increase each digit by one, you get another perfect square." What was the serial number?

13225

15114

14331