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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.

A334299 Number of distinct subsequences (not necessarily contiguous) of compositions in standard order (A066099).

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%I A334299 #10 Jun 04 2020 06:39:42
%S A334299 1,2,2,3,2,4,4,4,2,4,3,6,4,7,6,5,2,4,4,6,4,6,7,8,4,7,6,10,6,10,8,6,2,
%T A334299 4,4,6,3,8,8,8,4,8,4,9,8,12,11,10,4,7,8,10,8,11,12,13,6,10,9,14,8,13,
%U A334299 10,7,2,4,4,6,4,8,8,8,4,6,6,12,7,14,12,10,4
%N A334299 Number of distinct subsequences (not necessarily contiguous) of compositions in standard order (A066099).
%C A334299 The k-th composition in standard order (graded reverse-lexicographic, 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. This gives a bijective correspondence between nonnegative integers and integer compositions.
%F A334299 a(n) = A334300(n) + 1.
%e A334299 Triangle begins:
%e A334299   1
%e A334299   2
%e A334299   2 3
%e A334299   2 4 4 4
%e A334299   2 4 3 6 4 7 6 5
%e A334299   2 4 4 6 4 6 7 8 4 7 6 10 6 10 8 6
%e A334299 If the k-th composition in standard order is c, then we say that the STC-number of c is k. The n-th column below lists the STC-numbers of the subsequences of the composition with STC-number n:
%e A334299   0  1  2  3  4  5  6  7  8  9  10  11  12  13  14  15
%e A334299      0  0  1  0  2  2  3  0  4   2   5   4   6   6   7
%e A334299            0     1  1  1     1   0   3   1   5   3   3
%e A334299                  0  0  0     0       2   0   3   2   1
%e A334299                                      1       2   1   0
%e A334299                                      0       1   0
%e A334299                                              0
%t A334299 stc[n_]:=Differences[Prepend[Join@@Position[Reverse[IntegerDigits[n,2]],1],0]]//Reverse;
%t A334299 Table[Length[Union[Subsets[stc[n]]]],{n,0,100}]
%Y A334299 Row lengths are A011782.
%Y A334299 Looking only at contiguous subsequences gives A124771.
%Y A334299 Compositions where every subinterval has a different sum are A333222.
%Y A334299 Knapsack compositions are A333223.
%Y A334299 Contiguous positive subsequence-sums are counted by A333224.
%Y A334299 Contiguous subsequence-sums are counted by A333257.
%Y A334299 Disallowing empty subsequences gives A334300.
%Y A334299 Subsequence-sums are counted by A334968.
%Y A334299 Cf. A000120, A029931, A048793, A066099, A070939, A108917, A325676, A334967.
%K A334299 nonn
%O A334299 0,2
%A A334299 _Gus Wiseman_, Jun 01 2020