Results of a Chebyshev variant of what I described in http://list.seqfan.eu/pipermail/seqfan/2010-August/005643.html are gathered in http://www.strw.leidenuniv.nl/~mathar/public/mathar20100817.pdf which I perhaps shall update depending on various factors that I am too lazy to think about or describe in detail ... Richard Mathar