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 A097632 2^n * Lucas(n). 0
 2, 12, 64, 672, 8448, 138240, 2672640, 60641280, 1568931840, 45705461760, 1478924697600, 52646746521600, 2044394156851200, 86005817907609600, 3896481847600742400, 189139342470414336000, 9793081532749971456000 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Number of possible well-colored cycles on n nodes. Well-colored means, each green vertex has at least a red child, each red vertex has no red child. LINKS Table of n, a(n) for n=1..17. C. Banderier, J.-M. Le Bars and V. Ravelomanana, Generating functions for kernels of digraphs FORMULA E.g.f.: -log(1-2x-4x^2). Contrary to b(n) = 2^n*Fib(n), there seems to be no rational o.g.f. for the sequence. CROSSREFS Equals A000079(n) * A000204(n). Sequence in context: A226226 A126737 A345697 * A076804 A190153 A334772 Adjacent sequences: A097629 A097630 A097631 * A097633 A097634 A097635 KEYWORD nonn AUTHOR Ralf Stephan, Aug 17 2004 STATUS approved

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Last modified October 3 01:11 EDT 2023. Contains 365841 sequences. (Running on oeis4.)