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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A322367 Number of disconnected or empty integer partitions of n.

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%I A322367 #5 Dec 05 2018 07:58:34
%S A322367 1,0,1,2,3,6,7,14,17,27,34,54,63,98,118,165,207,287,345,474,574,757,
%T A322367 931,1212,1463,1890,2292,2898,3515,4413,5303
%N A322367 Number of disconnected or empty integer partitions of n.
%C A322367 An integer partition is connected if the prime factorizations of its parts form a connected hypergraph. It is disconnected if it can be separated into two or more integer partitions with relatively prime products. For example, the integer partition (654321) has three connected components: (6432)(5)(1).
%e A322367 The a(3) = 2 through a(9) = 27 disconnected integer partitions:
%e A322367   (21)   (31)    (32)     (51)      (43)       (53)        (54)
%e A322367   (111)  (211)   (41)     (321)     (52)       (71)        (72)
%e A322367          (1111)  (221)    (411)     (61)       (332)       (81)
%e A322367                  (311)    (2211)    (322)      (431)       (432)
%e A322367                  (2111)   (3111)    (331)      (521)       (441)
%e A322367                  (11111)  (21111)   (421)      (611)       (522)
%e A322367                           (111111)  (511)      (3221)      (531)
%e A322367                                     (2221)     (3311)      (621)
%e A322367                                     (3211)     (4211)      (711)
%e A322367                                     (4111)     (5111)      (3222)
%e A322367                                     (22111)    (22211)     (3321)
%e A322367                                     (31111)    (32111)     (4221)
%e A322367                                     (211111)   (41111)     (4311)
%e A322367                                     (1111111)  (221111)    (5211)
%e A322367                                                (311111)    (6111)
%e A322367                                                (2111111)   (22221)
%e A322367                                                (11111111)  (32211)
%e A322367                                                            (33111)
%e A322367                                                            (42111)
%e A322367                                                            (51111)
%e A322367                                                            (222111)
%e A322367                                                            (321111)
%e A322367                                                            (411111)
%e A322367                                                            (2211111)
%e A322367                                                            (3111111)
%e A322367                                                            (21111111)
%e A322367                                                            (111111111)
%t A322367 zsm[s_]:=With[{c=Select[Tuples[Range[Length[s]],2],And[Less@@#,GCD@@s[[#]]]>1&]},If[c=={},s,zsm[Sort[Append[Delete[s,List/@c[[1]]],LCM@@s[[c[[1]]]]]]]]];
%t A322367 Table[Length[Select[IntegerPartitions[n],Length[zsm[#]]!=1&]],{n,20}]
%Y A322367 Cf. A054921, A218970, A286518, A322335, A304714, A304716, A305078, A305079, A322306, A322307, A322337, A322338, A322368, A322369.
%K A322367 nonn,more
%O A322367 0,4
%A A322367 _Gus Wiseman_, Dec 04 2018