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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.

A355393 Number of integer partitions of n such that, for all parts x of multiplicity 1, either x - 1 or x + 1 is also a part.

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%I A355393 #6 Aug 26 2022 16:52:36
%S A355393 1,0,1,2,3,4,6,7,10,14,17,23,32,39,51,67,83,105,134,165,206,256,312,
%T A355393 385,475,573,697,849,1021,1231,1483,1771,2121,2534,3007,3575,4245,
%U A355393 5008,5914,6979,8198,9626,11292,13201,15430,18010,20960,24389,28346,32855,38066
%N A355393 Number of integer partitions of n such that, for all parts x of multiplicity 1, either x - 1 or x + 1 is also a part.
%C A355393 These are partitions without a neighborless singleton, where a part x is neighborless if neither x - 1 nor x + 1 are parts, and a singleton if it appears only once.
%e A355393 The a(0) = 1 through a(8) = 10 partitions:
%e A355393   ()  .  (11)  (21)   (22)    (32)     (33)      (43)       (44)
%e A355393                (111)  (211)   (221)    (222)     (322)      (332)
%e A355393                       (1111)  (2111)   (321)     (2221)     (2222)
%e A355393                               (11111)  (2211)    (3211)     (3221)
%e A355393                                        (21111)   (22111)    (3311)
%e A355393                                        (111111)  (211111)   (22211)
%e A355393                                                  (1111111)  (32111)
%e A355393                                                             (221111)
%e A355393                                                             (2111111)
%e A355393                                                             (11111111)
%t A355393 Table[Length[Select[IntegerPartitions[n],Function[ptn,!Or@@Table[Count[ptn,x]==1&&!MemberQ[ptn,x-1]&&!MemberQ[ptn,x+1],{x,Union[ptn]}]]]],{n,0,30}]
%Y A355393 This is the singleton case of A355394, complement A356236.
%Y A355393 The complement is counted by A356235.
%Y A355393 These partitions are ranked by the complement of A356237.
%Y A355393 The strict case is A356606, complement A356607.
%Y A355393 A000041 counts integer partitions, strict A000009.
%Y A355393 A000837 counts relatively prime partitions, ranked by A289509.
%Y A355393 A007690 counts partitions with no singletons, complement A183558.
%Y A355393 Cf. A073491, A325160, A328171, A328172, A328187, A328220, A356233.
%K A355393 nonn
%O A355393 0,4
%A A355393 _Gus Wiseman_, Aug 26 2022