Tony Padilla & Matt Parker: Graham's Number

• Maximum entropy that can be stored in your head
• Smax = A / 4L ^ 2
• L = 1.616 * 10 ^ -35m
• A = 4 * pi * r ^ 2
• 3↑3 = 3^3 = 3 * 3 * 3 = 27
• 3↑↑3 = 3↑(3↑3) = 3↑ (3 * 3 * 3) = 3↑27 = 3^27 = 7,625,597,484,987
• Knuth's up-arrow notation (クヌースの矢印表記)