%I A054922
%S A054922 2,0,0,10,164,2670,56724,1867860,104538928,10461483366,1912179618740,
%T A054922 644464839239880,402785011941549964,468944407349226545614,
%U A054922 1021179521951204217530900,4174755063830188009750183026
%N A054922 Number of connected unlabeled symmetric relations (graphs with loops) 
               having n nodes such that complement is also connected.
%H A054922 V. A. Liskovets, <a href="http://www.cs.uwaterloo.ca/journals/JIS/index.html">
               Some easily derivable sequences</a>, J. Integer Sequences, 3 (2000), 
               #00.2.2.
%F A054922 2*A054921(n)-A000666(n).
%Y A054922 Sequence in context: A000425 A010893 A000171 this_sequence A061848 A120556 
               A120560
%Y A054922 Adjacent sequences: A054919 A054920 A054921 this_sequence A054923 A054924 
               A054925
%K A054922 nonn,easy
%O A054922 1,1
%A A054922 N. J. A. Sloane (njas(AT)research.att.com), May 24 2000
%E A054922 More terms from Vladeta Jovovic (vladeta(AT)eunet.rs), Jul 17 2000