Wednesday, November 09, 2011

Turtle checksums

Here is a Turtle Art program that calculates the checksum of a South American 7 digit identity number. Source. You can get the algorithm as a spreadsheet

How many ID numbers share a checksum?
Find 2 ID numbers with the same checksum, not by trial and error
The 'key' is 2987634, what restrictions are there on the key that could be used?
What is the effect of having the digit 0 in the key?

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Saturday, November 05, 2011

RGB colour addition

Demonstrates colour addition using Turtle Blocks

vary the brightness of the colour circles, you could use the keyboard

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