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%I #11 Apr 18 2023 09:42:40
%S 0,1,3,9,25,75,235,759,2521,8555,29503,103129,364547,1300819,4679471,
%T 16952161,61790441,226451035,833918839,3084255127,11451630043,
%U 42669225171,159497648599,597950875255,2247724108771,8470205600639
%N Row sums of A047997.
%C Also the number of nonempty subsets of {1..2n} with mean n, even bisection of A362046. - _Gus Wiseman_, Apr 15 2023
%F From _Gus Wiseman_, Apr 15 2023: (Start)
%F a(n) = A000980(n)/2 - 1.
%F a(n) = A047653(n) - 1.
%F a(n) = A133406(2n+1) - 1.
%F a(n) = A362046(2n).
%F (End)
%e From _Gus Wiseman_, Apr 15 2023: (Start)
%e The a(1) = 1 through a(3) = 9 subsets:
%e {1} {2} {3}
%e {1,3} {1,5}
%e {1,2,3} {2,4}
%e {1,2,6}
%e {1,3,5}
%e {2,3,4}
%e {1,2,3,6}
%e {1,2,4,5}
%e {1,2,3,4,5}
%e (End)
%t Table[Length[Select[Subsets[Range[2n]],Mean[#]==n&]],{n,0,6}] (* _Gus Wiseman_, Apr 15 2023 *)
%Y Equals A047653(n) - 1.
%Y Row sums of A047997.
%Y For median instead of mean we have A079309, bisection of A361801.
%Y Even bisection of A362046, zero-based version A070925.
%Y A000980 counts nonempty subsets of {1..2n-1} with mean n.
%Y A007318 counts subsets by length.
%Y A327475 counts subsets with integer mean.
%Y A327481 counts subsets by mean.
%Y Cf. A000975, A013580, A024718, A057552, A133406, A361866.
%K nonn
%O 0,3
%A _N. J. A. Sloane_, May 16 2012
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