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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.

A384884 Number of integer partitions of n with all distinct lengths of maximal gapless runs (decreasing by 0 or 1).

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%I A384884 #8 Jun 14 2025 23:51:17
%S A384884 1,1,2,3,4,6,9,13,18,25,35,46,60,79,104,131,170,215,271,342,431,535,
%T A384884 670,830,1019,1258,1547,1881,2298,2787,3359,4061,4890,5849,7010,8361,
%U A384884 9942,11825,14021,16558,19561,23057,27084,31821,37312,43627,50999,59500,69267
%N A384884 Number of integer partitions of n with all distinct lengths of maximal gapless runs (decreasing by 0 or 1).
%e A384884 The partition y = (6,6,4,3,3,2) has maximal gapless runs ((6,6),(4,3,3,2)), with lengths (2,4), so y is counted under a(24).
%e A384884 The a(1) = 1 through a(8) = 18 partitions:
%e A384884   (1)  (2)   (3)    (4)     (5)      (6)       (7)        (8)
%e A384884        (11)  (21)   (22)    (32)     (33)      (43)       (44)
%e A384884              (111)  (211)   (221)    (222)     (322)      (332)
%e A384884                     (1111)  (311)    (321)     (331)      (422)
%e A384884                             (2111)   (411)     (421)      (431)
%e A384884                             (11111)  (2211)    (511)      (521)
%e A384884                                      (3111)    (2221)     (611)
%e A384884                                      (21111)   (3211)     (2222)
%e A384884                                      (111111)  (4111)     (3221)
%e A384884                                                (22111)    (4211)
%e A384884                                                (31111)    (5111)
%e A384884                                                (211111)   (22211)
%e A384884                                                (1111111)  (32111)
%e A384884                                                           (41111)
%e A384884                                                           (221111)
%e A384884                                                           (311111)
%e A384884                                                           (2111111)
%e A384884                                                           (11111111)
%t A384884 Table[Length[Select[IntegerPartitions[n],UnsameQ@@Length/@Split[#,#2>=#1-1&]&]],{n,0,15}]
%Y A384884 For subsets instead of strict partitions we have A384175.
%Y A384884 The strict case is A384178, for anti-runs A384880.
%Y A384884 For anti-runs we have A384885.
%Y A384884 For equal instead of distinct lengths we have A384887.
%Y A384884 A000041 counts integer partitions, strict A000009.
%Y A384884 A007690 counts partitions with no singletons, complement A183558.
%Y A384884 A034296 counts flat or gapless partitions, ranks A066311 or A073491.
%Y A384884 A098859 counts Wilf partitions (distinct multiplicities), complement A336866.
%Y A384884 A239455 counts Look-and-Say or section-sum partitions, ranks A351294 or A381432.
%Y A384884 A355394 counts partitions without a neighborless part, singleton case A355393.
%Y A384884 A356236 counts partitions with a neighborless part, singleton case A356235.
%Y A384884 A356606 counts strict partitions without a neighborless part, complement A356607.
%Y A384884 Cf. A008284, A044813, A047993, A242882, A287170, A325324, A325325, A356226, A356230, A356233, A356234, A384176, A384177, A384886.
%K A384884 nonn
%O A384884 0,3
%A A384884 _Gus Wiseman_, Jun 13 2025