Personalized Pi Day Math Symbol Celebration Party Newborn Layette. Celebrate Pi Day with a Newborn Layette - White featuring distressed look math symbol logo for students, engineers or a math teacher. 100% combed ringspun cotton 5.8 ounce 1×1 baby rib sleeper. 3/8" flatlock binding at envelope neck and cuffs. Back sleeve flap to protect hands. Elastic opening at bottom. Infant: 0-3 Months