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 A327481 Triangle read by rows where T(n,k) is the number of nonempty subsets of {1..n} with mean k. 9
 1, 1, 1, 1, 3, 1, 1, 3, 3, 1, 1, 3, 7, 3, 1, 1, 3, 9, 9, 3, 1, 1, 3, 9, 19, 9, 3, 1, 1, 3, 9, 25, 25, 9, 3, 1, 1, 3, 9, 29, 51, 29, 9, 3, 1, 1, 3, 9, 31, 75, 75, 31, 9, 3, 1, 1, 3, 9, 31, 93, 151, 93, 31, 9, 3, 1, 1, 3, 9, 31, 105, 235, 235, 105, 31, 9, 3, 1 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,5 COMMENTS All terms are odd. LINKS EXAMPLE Triangle begins:                          1                        1   1                      1   3   1                    1   3   3   1                  1   3   7   3   1                1   3   9   9   3   1              1   3   9  19   9   3   1            1   3   9  25  25   9   3   1          1   3   9  29  51  29   9   3   1        1   3   9  31  75  75  31   9   3   1      1   3   9  31  93 151  93  31   9   3   1    1   3   9  31 105 235 235 105  31   9   3   1 The subsets counted in row n = 5:   {1}  {2}      {3}          {4}      {5}        {1,3}    {1,5}        {3,5}        {1,2,3}  {2,4}        {3,4,5}                 {1,3,5}                 {2,3,4}                 {1,2,4,5}                 {1,2,3,4,5} MATHEMATICA Table[Length[Select[Subsets[Range[n]], Mean[#]==k&]], {n, 10}, {k, n}] CROSSREFS Row sums are A051293. The sequence of rows converges to A066571. The version for partitions is A327482. Cf. A000016, A063776, A065795, A135342, A327474, A327475, A327483, A327484. Sequence in context: A157454 A106255 A143086 * A152714 A174546 A134444 Adjacent sequences:  A327478 A327479 A327480 * A327482 A327483 A327484 KEYWORD nonn,tabl AUTHOR Gus Wiseman, Sep 13 2019 STATUS approved

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Last modified May 11 12:47 EDT 2021. Contains 343791 sequences. (Running on oeis4.)