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A362813 Number of numbers that occur more than once in column n of McGarvey's array (A007062).

%I A362813 #7 May 20 2023 15:48:37
%S A362813 0,2,3,4,6,6,7,9,11,12,14,13,14,16,15,17,21,20,22,25,24,25,29,26,26,
%T A362813 31,29,31,36,33,33,40,37,36,44,41,39,48,42,44,50,44,48,53,49,49,56,54,
%U A362813 53,62,55,56,69,61,59,66,61,66,73,65,64,75,71,70,80,72,71
%N A362813 Number of numbers that occur more than once in column n of McGarvey's array (A007062).
%e A362813 Corner of McGarvey's array (from A007062):
%e A362813    1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 16 17 18 19 20
%e A362813    2  1  4  3  6  5  8  7 10  9 12 11 14 13 16 15 18 17 20 19
%e A362813    4  1  2  5  6  3 10  7  8 11 12  9 16 13 14 17 18 15 22 19
%e A362813    5  2  1  4  7 10  3  6  9 12 11  8 17 14 13 16 19 22 15 18
%e A362813    7  4  1  2  5 12  8  6  3 10 13 14 17  8 11 18 15 22 19 16
%e A362813   12  5  2  1  4  7 14 13 10  3  6  8 22 15 18 11  8 17 24 23
%e A362813   14  7  4  1  2  5 12 15 22  8  6  3 10 13 20 23 24 17  8 11
%e A362813   15 12  5  2  1  4  7 14 23 20 13 10  3  6  8 22 25 28 31 18
%e A362813 (Column 3) = (3,4,2,1,1,2,4,5,7,12,23,...) in which the numbers 1,2,4 occur more than once.
%t A362813 a = Range[x = 40000]; rows = Table[a = Flatten[Map[Reverse, Partition[a, n]]], {n,
%t A362813    NestWhile[# + 1 &, 1, (x = # Floor[x/#]) > 0 &] - 1}];
%t A362813 Flatten[Table[{Length[Select[SortBy[Tally[Map[#[[col]] &, rows]], #[[2]] &], #[[2]] > 1 &]]}, {col, 100}]]  (* _Peter J. C. Moses_, May 01 2023 *)
%Y A362813 Cf. A007062, A309977.
%K A362813 nonn
%O A362813 1,2
%A A362813 _Clark Kimberling_, May 04 2023