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.
%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