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%I #9 Sep 04 2019 21:43:24
%S 1,3,10,103,727,2186,24061,625691,625719,10637349,202110261,202110426,
%T 4648540788,23242705227,69728116682,4044230782571,125371154379821,
%U 125371154410761,125371154418717,4638732713568111,4638732713587491,190188041257290621,8178085774065735093
%N a(n) = (1/C(0,0) + 1/C(2,1) + ... + 1/C(2n,n))*L, where L = LCM{C(0,0), C(2,1),..., C(2n,n)}.
%p a:= n-> (l-> add(1/j, j=l)*ilcm(l[]))([seq(binomial(2*i,i), i=0..n)]):
%p seq(a(n), n=0..22); # _Alois P. Heinz_, Sep 04 2019
%Y Cf. A000984.
%K nonn
%O 0,2
%A _Clark Kimberling_
%E a(7) corrected by _Sean A. Irvine_, Sep 04 2019