A353403 Number of compositions of n whose own reversed run-lengths are a subsequence (not necessarily consecutive).
1, 1, 0, 0, 3, 2, 5, 12, 16, 30, 45, 94, 159, 285, 477, 864, 1487, 2643
Offset: 0
Examples
The a(0) = 1 through a(7) = 12 compositions: () (1) . . (22) (1121) (1113) (1123) (112) (1211) (1122) (1132) (211) (1221) (2311) (2211) (3211) (3111) (11131) (11212) (11221) (12112) (12211) (13111) (21121) (21211)
Crossrefs
Programs
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Mathematica
Table[Length[Select[Join@@Permutations/@ IntegerPartitions[n],MemberQ[Subsets[#],Reverse[Length/@Split[#]]]&]],{n,0,15}]