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%I #5 Sep 02 2019 08:05:20
%S 1,1,1,1,2,4,14,49,234,1476,15405,307536,12651788,1044977929,
%T 167207997404,50838593828724,29156171171238607,31484900549777534887,
%U 64064043979274771429379,246064055301339083624989655
%N Number of unlabeled simple graphs with n vertices whose edge-set is not connected.
%F a(n) = 1 + A000088(n) - Sum_{i = 1..n} A001349(i).
%e The a(4) = 2 through a(6) = 14 edge-sets:
%e {} {} {}
%e {12,34} {12,34} {12,34}
%e {12,35,45} {12,34,56}
%e {12,34,35,45} {12,35,45}
%e {12,34,35,45}
%e {12,35,46,56}
%e {12,36,46,56}
%e {13,23,46,56}
%e {12,34,35,46,56}
%e {12,36,45,46,56}
%e {13,23,45,46,56}
%e {12,13,23,45,46,56}
%e {12,35,36,45,46,56}
%e {12,34,35,36,45,46,56}
%Y Unlabeled non-connected graphs are A000719.
%Y Partial sums of A327075.
%Y The labeled version is A327199.
%Y Cf. A000088, A001349, A002494, A052446, A054592, A327070, A327071.
%K nonn
%O 0,5
%A _Gus Wiseman_, Sep 01 2019
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