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%I #5 May 19 2018 12:59:27
%S 1,0,2,2,7,12,32,67,169,390,985,2412,6209,15871,41867,110797,299836,
%T 817612,2268640,6354409,18058764,51838340,150704087,442550971,
%U 1314527780,3943140077,11953192954,36580095663,113048257691,352564213025,1109727658303
%N Number of partitions of n that contain exactly two isolated singletons.
%H A. O. Munagi, <a href="https://doi.org/10.1080/00029890.2018.1430960">Set partitions with isolated singletons</a>, Am. Math. Monthly 125 (2018), 447-452.
%p f:=proc(n,r) local j;
%p add(combinat:-bell(j-1)*binomial(n-j-1,j-r-1),j=1..floor((n+r)/2));
%p end;
%p [seq(f(n,2),n=2..40)];
%Y Cf. A303586, A303587.
%K nonn
%O 2,3
%A _N. J. A. Sloane_, May 19 2018