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%I #26 Jan 20 2020 13:29:58
%S 0,0,0,0,0,0,8,144,3552,131452,7840396,797524408
%N Number of simple disconnected asymmetric graph on n vertices.
%C For 2 < n < 12, a(n) = A124059(n-1) (connected asymmetric graphs). This is because the singleton is the only asymmetric graph with fewer than 6 vertices, so in a disconnected asymmetric graph with fewer than 12 vertices one connected component must be the singleton, and it cannot occur more than once. - _Falk Hüffner_, Jan 16 2020
%D 1
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/GraphAutomorphism.html">Graph Automorphism</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/IdentityGraph.html">Identity Graph</a>
%F a(n) = A003400(n) - A124059(n).
%t A[s_Integer] := With[{s6 = StringPadLeft[ToString[s], 6, "0"]}, Cases[ Import[ "https://oeis.org/A" <> s6 <> "/b" <> s6 <> ".txt", "Table"], {_, _}][[All, 2]]];
%t A003400 = A@003400;
%t A124059 = A@124059;
%t a[n_] := A003400[[n]] - A124059[[n]];
%t a /@ Range[12] (* _Jean-François Alcover_, Jan 07 2020 *)
%Y Cf. A003400 (not-necessarily connected simple asymmetric graphs).
%Y Cf. A124059 (connected simple asymmetric graphs).
%K nonn
%O 1,7
%A _Eric W. Weisstein_, May 19 2017
%E a(12) from _Jean-François Alcover_, Jan 07 2020
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