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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.

A356236 Number of integer partitions of n with a neighborless part.

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%I A356236 #11 Feb 17 2024 14:08:09
%S A356236 0,1,2,2,4,4,8,9,16,20,31,40,59,76,105,138,184,238,311,400,515,656,
%T A356236 831,1052,1322,1659,2064,2572,3182,3934,4837,5942,7264,8872,10789,
%U A356236 13109,15865,19174,23105,27796,33361,39956,47766,56985,67871,80675,95750,113416
%N A356236 Number of integer partitions of n with a neighborless part.
%C A356236 A part x of a partition is neighborless if neither x - 1 nor x + 1 are parts.
%F A356236 a(n) = A000041(n) - A355394(n).
%e A356236 The a(1) = 1 through a(8) = 9 partitions:
%e A356236   (1)  (2)   (3)    (4)     (5)      (6)       (7)
%e A356236        (11)  (111)  (22)    (41)     (33)      (52)
%e A356236                     (31)    (311)    (42)      (61)
%e A356236                     (1111)  (11111)  (51)      (331)
%e A356236                                      (222)     (421)
%e A356236                                      (411)     (511)
%e A356236                                      (3111)    (4111)
%e A356236                                      (111111)  (31111)
%e A356236                                                (1111111)
%t A356236 Table[Length[Select[IntegerPartitions[n],Function[ptn,Or@@Table[!MemberQ[ptn,x-1]&&!MemberQ[ptn,x+1],{x,Union[ptn]}]]]],{n,0,30}]
%Y A356236 The complement is counted by A355394, singleton case A355393.
%Y A356236 The singleton case is A356235, ranked by A356237.
%Y A356236 The strict case is A356607, complement A356606.
%Y A356236 These partitions are ranked by the complement of A356736.
%Y A356236 A000041 counts integer partitions, strict A000009.
%Y A356236 A000837 counts relatively prime partitions, ranked by A289509.
%Y A356236 A007690 counts partitions with no singletons, complement A183558.
%Y A356236 Cf. A066205, A112798, A319630, A325160, A328171, A328172, A328187, A328221.
%K A356236 nonn
%O A356236 0,3
%A A356236 _Gus Wiseman_, Aug 24 2022