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%I #5 Aug 27 2024 09:14:32
%S 0,0,0,0,0,0,0,0,0,1,6,21,68,199,545,1410,3530,8557,20255,46968,
%T 107135,240927,535379,1177435,2566618,5551456
%N Number of integer compositions of n matching both of the dashed patterns 23-1 and 1-32.
%C Also the number of integer compositions of n whose leaders of maximal weakly increasing runs are not weakly decreasing and whose reverse satisfies the same condition.
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Permutation_pattern">Permutation pattern</a>.
%H Gus Wiseman, <a href="/A374629/a374629.txt">Sequences counting and ranking compositions by their leaders (for six types of runs)</a>.
%e The a(0) = 0 through a(11) = 21 compositions:
%e . . . . . . . . . (12321) (1342) (1352)
%e (2431) (2531)
%e (12421) (11342)
%e (13231) (12431)
%e (112321) (12521)
%e (123211) (13241)
%e (13421)
%e (14231)
%e (23132)
%e (24311)
%e (112421)
%e (113231)
%e (122321)
%e (123212)
%e (123221)
%e (124211)
%e (132311)
%e (212321)
%e (1112321)
%e (1123211)
%e (1232111)
%t Table[Length[Select[Join@@Permutations/@IntegerPartitions[n], MatchQ[#,{___,y_,z_,___,x_,___}/;x<y<z]&&MatchQ[#,{___,x_,___,z_,y_,___}/;x<y<z]&]],{n,0,15}]
%Y For leaders of identical runs we have A332834.
%Y For just one of the two conditions we have A374636, ranks A375137/A375138.
%Y These compositions are ranked by A375407.
%Y A003242 counts anti-runs, ranks A333489.
%Y A011782 counts compositions.
%Y A106356 counts compositions by number of maximal anti-runs.
%Y A238130, A238279, A333755 count compositions by number of runs.
%Y A274174 counts contiguous compositions, ranks A374249.
%Y A335456 counts patterns matched by compositions.
%Y Cf. A000041, A056823, A188920, A189076, A238343, A333213, A335514, A374631, A374632, A374635, A374681.
%K nonn,more,new
%O 0,11
%A _Gus Wiseman_, Aug 23 2024
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