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 A212149 Number of k-element subsets S of {1,...,n} such that mean(S)
 0, 0, 0, 1, 4, 13, 34, 82, 185, 403, 853, 1777, 3656, 7465, 15156, 30659, 61850, 124548, 250456, 503158 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,5 COMMENTS Also the number of k-element subsets S of {1,...,n} such that mean(S)>median(S).  A212149(n) = A212140(n)/2. LINKS MATHEMATICA t[n_, k_] := t[n, k] = Count[Map[Median[#] == Mean[#] &, Subsets[Range[n], {k}]], False] Flatten[Table[t[n, k], {n, 1, 12}, {k, 1, n}]] TableForm[Table[t[n, k], {n, 1, 12}, {k, 1, n}]] s[n_] := Sum[t[n, k], {k, 1, n}] Table[s[n], {n, 1, 20}] (* A212140 *) %/2                     (* A212149 *) (* Peter J. C. Moses, May 01 2012 *) CROSSREFS Cf. A212139, A212140. Sequence in context: A029860 A262200 A213578 * A208740 A127981 A296303 Adjacent sequences:  A212146 A212147 A212148 * A212150 A212151 A212152 KEYWORD nonn AUTHOR Clark Kimberling, May 06 2012 STATUS approved

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Last modified December 6 18:16 EST 2021. Contains 349567 sequences. (Running on oeis4.)