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A348612 Numbers k such that the k-th composition in standard order is not an anti-run, i.e., has adjacent equal parts.

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%I A348612 #8 Nov 04 2021 11:09:11
%S A348612 3,7,10,11,14,15,19,21,23,26,27,28,29,30,31,35,36,39,42,43,46,47,51,
%T A348612 53,55,56,57,58,59,60,61,62,63,67,71,73,74,75,78,79,83,84,85,86,87,90,
%U A348612 91,92,93,94,95,99,100,103,106,107,110,111,112,113,114,115,116
%N A348612 Numbers k such that the k-th composition in standard order is not an anti-run, i.e., has adjacent equal parts.
%C A348612 First differs from A345168 in lacking 37, corresponding to the composition (3,2,1).
%C A348612 A composition of n is a finite sequence of positive integers summing to n. The k-th composition in standard order (row k of A066099) is obtained by taking the set of positions of 1's in the reversed binary expansion of k, prepending 0, taking first differences, and reversing again.
%e A348612 The terms and corresponding standard compositions begin:
%e A348612      3: (1,1)          35: (4,1,1)        61: (1,1,1,2,1)
%e A348612      7: (1,1,1)        36: (3,3)          62: (1,1,1,1,2)
%e A348612     10: (2,2)          39: (3,1,1,1)      63: (1,1,1,1,1,1)
%e A348612     11: (2,1,1)        42: (2,2,2)        67: (5,1,1)
%e A348612     14: (1,1,2)        43: (2,2,1,1)      71: (4,1,1,1)
%e A348612     15: (1,1,1,1)      46: (2,1,1,2)      73: (3,3,1)
%e A348612     19: (3,1,1)        47: (2,1,1,1,1)    74: (3,2,2)
%e A348612     21: (2,2,1)        51: (1,3,1,1)      75: (3,2,1,1)
%e A348612     23: (2,1,1,1)      53: (1,2,2,1)      78: (3,1,1,2)
%e A348612     26: (1,2,2)        55: (1,2,1,1,1)    79: (3,1,1,1,1)
%e A348612     27: (1,2,1,1)      56: (1,1,4)        83: (2,3,1,1)
%e A348612     28: (1,1,3)        57: (1,1,3,1)      84: (2,2,3)
%e A348612     29: (1,1,2,1)      58: (1,1,2,2)      85: (2,2,2,1)
%e A348612     30: (1,1,1,2)      59: (1,1,2,1,1)    86: (2,2,1,2)
%e A348612     31: (1,1,1,1,1)    60: (1,1,1,3)      87: (2,2,1,1,1)
%t A348612 stc[n_]:=Differences[Prepend[Join@@Position[Reverse[IntegerDigits[n,2]],1],0]]//Reverse;
%t A348612 Select[Range[100],MatchQ[stc[#],{___,x_,x_,___}]&]
%Y A348612 Constant run compositions are counted by A000005, ranked by A272919.
%Y A348612 Counting these compositions by sum and length gives A131044.
%Y A348612 These compositions are counted by A261983.
%Y A348612 The complement is A333489, counted by A003242.
%Y A348612 The non-alternating case is A345168, complement A345167.
%Y A348612 A011782 counts compositions, strict A032020.
%Y A348612 A238279 counts compositions by sum and number of maximal runs.
%Y A348612 A274174 counts compositions with equal parts contiguous.
%Y A348612 A336107 counts non-anti-run permutations of prime factors.
%Y A348612 A345195 counts non-alternating anti-runs, ranked by A345169.
%Y A348612 For compositions in standard order (rows of A066099):
%Y A348612 - Length is A000120.
%Y A348612 - Sum is A070939
%Y A348612 - Maximal runs are counted by A124767.
%Y A348612 - Strict compositions are ranked by A233564.
%Y A348612 - Maximal anti-runs are counted by A333381.
%Y A348612 - Runs-resistance is A333628.
%Y A348612 Cf. A029931, A048793, A106356, A114901, A167606, A178470, A228351, A244164, A262046, A335452, A335464.
%K A348612 nonn
%O A348612 1,1
%A A348612 _Gus Wiseman_, Nov 03 2021