A089417 - OEIS

%I #7 Mar 31 2012 14:02:17

%S 1,1,1,2,7,6,10,20,37,70,130,272,480,954,1750,3462,6481,12922,24372,

%T 48702,92490

%N Number of cycles in range [A014137(n-1)..A014138(n-1)] of permutation A082333/A082334.

%C The number of orbits to which the corresponding automorphism(s) partitions the set of A000108(n) binary trees with n internal nodes.

%C Is the non-monotone notch from a(4)=7 to a(5)=6 the only one?

%H A. Karttunen, <a href="/A089408/a089408.c.txt">C-program for computing the initial terms of this sequence</a>

%Y Cf. A089411.

%K nonn

%O 0,4

%A _Antti Karttunen_, Nov 29 2003, Proposed by _Wouter Meeussen_, Spring 2003.