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 A089880 Number of cycles in range [A014137(n-1)..A014138(n-1)] of permutation A069772. 2
 1, 1, 2, 3, 10, 22, 76, 217, 750, 2438, 8524, 29414, 104468, 371516, 1338936, 4847637, 17685270, 64823110, 238843660, 883634026, 3282152588, 12233141908, 45741634536, 171529836218, 644953425740, 2430973304732, 9183681736376 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS The number of orbits to which the corresponding automorphism(s) partitions the set of A000108(n) binary trees with n internal nodes. LINKS FORMULA a(n) = (A000108(n)+A089849(n))/2 PROG (Scheme) (define (A089880 n) (/ (+ (A000108 n) (A089849 n)) 2)) CROSSREFS Sequence in context: A148057 A148058 A148059 * A130002 A162034 A105286 Adjacent sequences:  A089877 A089878 A089879 * A089881 A089882 A089883 KEYWORD nonn,easy AUTHOR Antti Karttunen, Nov 29 2003 STATUS approved

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Last modified November 21 12:34 EST 2017. Contains 295001 sequences.