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%I #6 May 21 2018 11:26:28
%S 1,2,5,18,104,943,12133,203038,4177755,101922814,2874725600,
%T 92009680557,3294276613933,130446181101044,5660055256165565,
%U 267044522107706072,13611243187516647324,745329728016955480687,43636132793651444511809,2719977663069107176768790
%N Number of labeled antichain hyperforests spanning a subset of {1,...,n}.
%F Binomial transform of A134954.
%e The a(3) = 18 hyperforests are the following:
%e {{1,2,3}} {{2,3}} {{1,3}} {{1,2}} {{3}} {{2}} {{1}} {}
%e {{1,3},{2,3}} {{2},{3}} {{1},{3}} {{1},{2}}
%e {{1,2},{2,3}}
%e {{1,2},{1,3}}
%e {{3},{1,2}}
%e {{2},{1,3}}
%e {{1},{2,3}}
%e {{1},{2},{3}}
%Y Cf. A030019, A035053, A048143, A134954, A134955, A134957, A134956, A134957, A134959, A144959, A303838, A304716, A304717, A304867, A304911, A304912.
%K nonn
%O 0,2
%A _Gus Wiseman_, May 21 2018