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If this issue's Puzzle page whets your appetite for solving mathematical puzzles online then you might like to look at a new internet journal, Interact, published by the NRICH Maths project.
The journal, updated monthly, features a collection of problems designed to get you thinking. The problems are aimed at gifted 11-13 year olds and represents the first part of an experiment in extending the Royal Institution's series of Mathematics Masterclasses into the WWW. However, the NRICH team hope to extend the site to include material to appeal to budding mathematicians of all ages over the coming months.