Tetration sites with peer reviewed information
Check out Ioannis Galidakis for his recent papers including On Extending hyper4 and Knuth's Up-arrow Notation to the Reals
Galidakis, Ioannis and Eric W. Weisstein,
Power Tower , From MathWorld--A Wolfram Web Resource
Nice website on background information relevant to tetration, with new content
constantly being added.
Will Jagy has a web site with a number of preprints of articles relating to the convergence of fractionally iterated functions.
MacDonnell, J. F.
Some Critical Points of the Hyperpower Function,
International Journal of Mathematical Education, 1989, Vol. 20, #2, p.297
Informally peer reviewed
mathoverflow.net Very active site. Note: only for graduate level math. Read FAQ before posting.
sci.math.research Number of good discussions on tetration research.
Tetration Forum Site on tetration research.
Other tetration sites
Andrew Robbins' Tetration web site.
Robbins has proposed a way to extend tetration to the real numbers.
Dmitrii Kouznetsov's Tetration and superlog web site.
Kouznetsov has also proposed a way of extending tetration.
Gottfried Helms' Tetration web site.
Helms has done considerable research and computation on tetration and related subjects.
Wikipedia: Tetration I no longer recommend the Wikipedia: Tetration article.
The article seriously violates Wikipedia's no unpublished research rule.
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