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Prime Exponent

As a budding physics major, I took Math 11 in 1955 as one of my first required courses. It was common knowledge that the Reed math courses were not going to help us solve physics problems, so practical math also was taught. I never did well at math department offerings. I believe my supreme agony occurred under Prof. Joe Roberts’ patient nurturing the following year). Nevertheless, I did learn some useful rules along the way. Let me stylize 2 squared as 2^2 and 2 cubed as 2^3 = 2 x 2 x 2. The article “Prime Exponent” noted that Prof. Roberts retired after teaching 2^(2^3) - 2 years. However, 2^3 is 2 x 2 x 2 = 8, and 2^8 now becomes 2 x 2 x 2 x 2 x 2 x 2 x 2 x 2 = 256, so 2^8 - 2 = 254 years. I’d like to think that the purity of mathematics could lead to such longevity, but suspect that what you meant was (2^2)^3, or (2 squared) to the 3rd power = (4 x 4 x 4), or 64 – 2 = 62. With exponents you work backwards, or downwards, from the last one. Simple as this all seems, it is perhaps one of the few times I did anything correct with reference to math and Reed.

—Roger Moment ’59
Longmont, Colorado

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Our postman brought the September 2014 Reed magazine to our house on his motorcycle this morning. Skimming through, I noticed something rather odd in the article about Prof. Joe Roberts: he taught at Reed for 254 years! Yes, that is the figure indicated in the subtitle, because 2 cubed = 8 and thus 2 to the 8th minus 2 = 256 - 2 = 254. Then again, perhaps we should be embarrassed, rather than amazed, that the writer, headline editor, and you all seemed to think 2 to the 2 to the 3 = 2 to the 6th or 64. This is what happens when our society at large disses basic calculation as mere “bean counting.”

—Martin Schell MAT ’77

Klaten, Central Java