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%I #36 Aug 03 2023 21:00:19
%S 1,1,2,5,10,37,60,295,658,2621,5368,38535,66506,551529,1234264,
%T 5004697,13721836,143935131,256835337,2971237021,6485081140,
%U 35162930303,95872321543,1315397878401,2399236456202,25866803180347,72374386475590,563368417647305,1479943119911866
%N Number of set partitions of [n] where the elements of each non-singleton block are pairwise coprime.
%C Two or more numbers are pairwise coprime if no pair of them has a common divisor > 1.
%H Alois P. Heinz, <a href="/A320430/b320430.txt">Table of n, a(n) for n = 0..38</a>
%e The a(4) = 10 set partitions: 1|2|3|4, 14|2|3, 13|2|4, 12|3|4, 1|23|4, 1|2|34, 134|2, 123|4, 14|23, 12|34.
%t spsu[_,{}]:={{}};spsu[foo_,set:{i_,___}]:=Join@@Function[s,Prepend[#,s]&/@spsu[Select[foo,Complement[#,Complement[set,s]]=={}&],Complement[set,s]]]/@Cases[foo,{i,___}];
%t Table[Length[spsu[Select[Subsets[Range[n]],Length[#]==1||CoprimeQ@@#&],Range[n]]],{n,10}]
%Y Cf. A000110, A000258, A008277, A051424, A085945, A186974, A187106, A302569, A303139, A320424, A320426, A320423, A333517.
%K nonn
%O 0,3
%A _Gus Wiseman_, Jan 08 2019
%E a(14)-a(15) from _Alois P. Heinz_, Jan 08 2019
%E a(16) from _Alois P. Heinz_, Mar 26 2020
%E a(17)-a(24) from _Giovanni Resta_, Mar 27 2020
%E a(25)-a(28) from _Alois P. Heinz_, Aug 03 2023
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