This roundabout road sign is in Bisbee, Arizona.

The roundabout road sign says...

+--------------------------+ | West AZ-80 | | West AZ-92 | | Sierra Vista East AZ-80 | +--------------------------+the numbers are: 92 80 80 the math is: none found do borrowing: take 2 away from 92 and assign 1 to each 80 the numbers become: 90 81 81 the math is: 90 - 81 = sqrt(81) off-by-one spf(n) math: spf(92) = spf(80) + spf(80) + 1 observe... spf(92) = 2 + 2 + 23 = 27 spf(80) = 2 + 2 + 2 + 2 + 5 = 13 spf(80) + spf(80) = 13 + 13 = 26

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

**Created:** 31 December 2007

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