This road sign was found on Pi Day 2009 on eastbound I-8 in Arizona.

The road sign says...

+----------------------+ | Casa Grande 13 | | Jct I-10 16 | | Tucson 74 | +----------------------+the numbers are: 13 10 16 74 rsAgeEval: 74 / sqrt(sqrt(16)) + 13 + log(10) = 51 more math: 13 + 16 - (74 - summation(10, 13)) = log(10) * summation(10, 13) = 10 + 11 + 12 + 13 = 46 more math: spf(74) - 13 - 16 = 10 * prime factors of 74 are 2 and 37 * spf(74) = sum_prime_factors(74) = 2 + 37 = 39 number system rsHwyEval: 13 - sqrt((16 + 74) / 10) = 10_{2}* This road sign is on I-8 number system math: 74_{8}/ 10 = (16 - 13)! * 74_{8}= 7 * 8 + 4 * 1 = 56 + 4 = 60 number system math: 74 - summation(13, 16) = 10_{16}number system math: summation(sqrt(sqrt(16)), 13) - 74 = 10_{16}

**Creator:** Gerald Thurman
[gthurman@gmail.com]

**Created:** 13 April 2009

This work is licensed under a Creative Commons Attribution 3.0 United States License.