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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.

A329743 Number of compositions of n with runs-resistance n - 3.

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%I A329743 #6 Nov 21 2019 22:14:59
%S A329743 0,0,0,1,2,6,9,16,8
%N A329743 Number of compositions of n with runs-resistance n - 3.
%C A329743 A composition of n is a finite sequence of positive integers with sum n.
%C A329743 For the operation of taking the sequence of run-lengths of a finite sequence, runs-resistance is defined as the number of applications required to reach a singleton.
%e A329743 The a(3) = 1 through a(8) = 8 compositions:
%e A329743   (3)  (22)    (14)   (114)    (1123)    (12113)
%e A329743        (1111)  (23)   (411)    (1132)    (12212)
%e A329743                (32)   (1113)   (1141)    (13112)
%e A329743                (41)   (1221)   (1411)    (21131)
%e A329743                (131)  (2112)   (2122)    (21221)
%e A329743                (212)  (3111)   (2212)    (31121)
%e A329743                       (11112)  (2311)    (121112)
%e A329743                       (11211)  (3211)    (211121)
%e A329743                       (21111)  (11131)
%e A329743                                (11212)
%e A329743                                (11221)
%e A329743                                (12211)
%e A329743                                (13111)
%e A329743                                (21211)
%e A329743                                (111121)
%e A329743                                (121111)
%e A329743 For example, repeatedly taking run-lengths starting with (1,2,1,1,3) gives (1,2,1,1,3) -> (1,1,2,1) -> (2,1,1) -> (1,2) -> (1,1) -> (2), which is 5 steps, and 5 = 8 - 3, so (1,2,1,1,3) is counted under a(8).
%t A329743 runsres[q_]:=If[Length[q]==1,0,Length[NestWhileList[Length/@Split[#]&,q,Length[#]>1&]]-1];
%t A329743 Table[Length[Select[Join@@Permutations/@IntegerPartitions[n],runsres[#]==n-3&]],{n,10}]
%Y A329743 Column k = n - 3 of A329744.
%Y A329743 Column k = 3 of A329750.
%Y A329743 Compositions with runs-resistance 2 are A329745.
%Y A329743 Cf. A000740, A008965, A098504, A242882, A318928, A329746, A329747, A329767.
%K A329743 nonn,fini,full
%O A329743 0,5
%A A329743 _Gus Wiseman_, Nov 21 2019