Mar 092016

This is going to be another one of my “selfish” posts – written primarily for me to refer back to in the future and not because I believe it will benefit anyone other than me. The idea is one that I always took for granted but had a hard time proving to myself once I decided to try.

Theorem: Suppose we have an M bit unsigned binary integer with value A. Consider the first (least significant) N bits with value B. Then:

A \equiv B \bmod{2^N}

Put another way, arithmetic with unsigned binary integers of a fixed length N is always performed modulo 2^N.
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Oct 022005

MIT's $100 LaptopNicholoas Negroponte, chairman of the Massachusetts Institute of Technology’s Media Lab, spoke recently at their annual Emerging Technologies Conference confirming that MIT is planning to provide low cost computers to underprivileged children in developing countries globally as well as to students here in the U.S. The One Laptop per Child nonprofit group is the offshoot of the Media Lab that will handle coordinating this ambitious plan. Five countries have already committed to participating including Brazil, China, Egypt, South Africa, and Thailand. Massachusetts is the first state to discuss using these machines in it’s public schools.

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