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 A275780 Number of set partitions of [n] into blocks with distinct element sums. 22
 1, 1, 2, 4, 12, 43, 160, 668, 3098, 15465, 83100, 477651, 2914505, 18795814, 127790544, 911448954, 6808162094 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 LINKS FORMULA a(n) = A000110(n) - A275781(n). EXAMPLE a(3) = 4: 123, 13|2, 1|23, 1|2|3. a(4) = 12: 1234, 123|4, 124|3, 12|34, 134|2, 13|24, 1|234, 1|23|4, 14|2|3, 1|24|3, 1|2|34, 1|2|3|4. MATHEMATICA sps[{}]:={{}}; sps[set:{i_, ___}]:=Join@@Function[s, Prepend[#, s]&/@sps[Complement[set, s]]]/@Cases[Subsets[set], {i, ___}]; Table[Length[Select[sps[Range[n]], UnsameQ@@Total/@#&]], {n, 0, 10}] (* Gus Wiseman, Jul 13 2019 *) CROSSREFS Cf. A000110, A007837, A035470, A038041, A275781, A278339, A321469, A326512, A326513, A326519, A326535. Sequence in context: A096802 A139669 A179973 * A334272 A348926 A039301 Adjacent sequences:  A275777 A275778 A275779 * A275781 A275782 A275783 KEYWORD nonn,more AUTHOR Alois P. Heinz, Aug 08 2016 STATUS approved

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Last modified December 9 08:41 EST 2021. Contains 349627 sequences. (Running on oeis4.)