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The Bird Tree

Published online by Cambridge University Press:  14 September 2009

RALF HINZE
RALF HINZE*
Affiliation:
Computing Laboratory, University of Oxford, Wolfson Building, Parks Road, Oxford, OX1 3QD, England (e-mail: ralf.hinze@comlab.ox.ac.uk)
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Sadly, Richard Bird is stepping down as the editor of the ‘Functional Pearls’ column. As a farewell present, I would like to dedicate a tree to him. A woody plant is appropriate for at least two reasons: Richard has been preoccupied with trees in many of his pearls, and where else would you find a bird's nest? Actually, there is a lot of room for nests, as the tree is infinite. Figure 1 displays the first five levels. The Bird tree, whose nodes are labelled with rational numbers, enjoys several remarkable properties.

Type
Functional Pearls
Information
Journal of Functional Programming , Volume 19 , Issue 5 , September 2009 , pp. 491 - 508
Copyright
Copyright © Cambridge University Press 2009

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