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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.

A384178 Number of strict integer partitions of n with all distinct lengths of maximal runs (decreasing by 1).

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%I A384178 #9 Jun 14 2025 23:51:08
%S A384178 1,1,1,2,1,2,2,3,3,4,5,6,6,8,8,10,11,13,13,16,15,19,19,23,22,26,28,31,
%T A384178 35,39,37,47,51,52,60,65,67,78,85,86,99,108,110,127,136,138,159,170,
%U A384178 171,196,209,213,240,257,260,292,306,313,350,371,369,417,441
%N A384178 Number of strict integer partitions of n with all distinct lengths of maximal runs (decreasing by 1).
%e A384178 The strict partition y = (9,7,6,5,2,1) has maximal runs ((9),(7,6,5),(2,1)), with lengths (1,3,2), so y is counted under a(30).
%e A384178 The a(1) = 1 through a(14) = 8 strict partitions (A-E = 10-14):
%e A384178   1  2  3   4  5   6    7    8    9    A     B     C     D     E
%e A384178         21     32  321  43   431  54   532   65    543   76    653
%e A384178                         421  521  432  541   542   651   643   743
%e A384178                                   621  721   632   732   652   761
%e A384178                                        4321  821   921   832   932
%e A384178                                              5321  6321  A21   B21
%e A384178                                                          5431  5432
%e A384178                                                          7321  8321
%t A384178 Table[Length[Select[IntegerPartitions[n],UnsameQ@@#&&UnsameQ@@Length/@Split[#,#1==#2+1&]&]],{n,0,30}]
%Y A384178 For subsets instead of strict partitions we have A384175, complement A384176.
%Y A384178 For anti-runs instead of runs we have A384880.
%Y A384178 This is the strict version of A384884.
%Y A384178 For equal instead of distinct lengths we have A384886.
%Y A384178 A000041 counts integer partitions, strict A000009.
%Y A384178 A047993 counts partitions with max part = length.
%Y A384178 A098859 counts Wilf partitions (complement A336866), compositions A242882.
%Y A384178 A239455 counts Look-and-Say or section-sum partitions, ranks A351294 or A381432.
%Y A384178 A351293 counts non-Look-and-Say or non-section-sum partitions, ranks A351295 or A381433.
%Y A384178 Cf. A008284, A044813, A325324, A325325, A329739, A351202.
%K A384178 nonn
%O A384178 0,4
%A A384178 _Gus Wiseman_, Jun 12 2025