number pi with 140 decimal places - white chalk text on a slate blackboard, mathematics and pi day concept

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Size: 5600px × 3735px
Photo credit: © Marek Uliasz / Alamy / Afripics
License: Royalty Free
Model Released: No

Keywords: 14, 314, abstract, blackboard, chalk, chalkboard, classroom, constant, day, easel, education, march, math, mathematics, number, numbers, pen, pi, retro, rustic, science, series, sign, wood