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%I #19 Dec 23 2024 14:53:45
%S 1,1,1,2,3,7,12,30,64,177,457,1403,4327,15024,54730,219311,942908,
%T 4426513,22525015,124896794,752933593,4938212176,35190683416,
%U 272266028155,2284292635109
%N Number of connected squarefree bipartite graphs on n vertices.
%H CombOS - Combinatorial Object Server, <a href="http://combos.org/nauty">Generate graphs</a>
%H Brendan McKay, <a href="https://web.archive.org/web/*/http://list.seqfan.eu/oldermail/seqfan/2018-March/018436.html">Inverse Euler transforms needed</a>, message on the SeqFan list, Mar 12 2018.
%F Inverse Euler transform of A138347.
%Y Cf. A138347.
%K nonn,more
%O 1,4
%A _Alois P. Heinz_, Mar 11 2018.