%I A078592
%S A078592 1,1,2,8,42,273,1970,15368,126510,1086546,9652364,88172609,824506191,7865294687,
%T A078592 76331857094,751981532942,7506432993145,75811326673326,773682540353704,
%U A078592 7969986193751019,82798726340037900,866804540900696571
%N A078592 Call two meanders from A005316 with 2n crossings equivalent if they differ 
               by reflections in the X or Y axes. Sequence gives number of inequivalent 
               meanders.
%C A078592 Symmetry group has order 4.
%F A078592 a(n) = (A005316(2n)+A005316(n))/2.
%Y A078592 Sequence in context: A005315 A121635 A002874 this_sequence A052646 A002856 
               A093461
%Y A078592 Adjacent sequences: A078589 A078590 A078591 this_sequence A078593 A078594 
               A078595
%K A078592 nonn
%O A078592 0,3
%A A078592 N. J. A. Sloane (njas(AT)research.att.com) and Jon Wild (wild(AT)music.mcgill.ca), 
               Dec 08 2002