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A223815 T(n,k)=Number of nXk 0..2 arrays with row sums nondecreasing and column sums unimodal.

%I A223815 #6 Jul 23 2025 04:33:37
%S A223815 3,9,6,22,50,10,46,337,222,15,86,1922,4120,867,21,148,9783,65465,
%T A223815 43941,3123,28,239,45537,921010,1941904,426527,10660,36,367,198252,
%U A223815 11789302,76453838,52310070,3875213,35064,45,541,817482,139965348,2740448352
%N A223815 T(n,k)=Number of nXk 0..2 arrays with row sums nondecreasing and column sums unimodal.
%C A223815 Table starts
%C A223815 ..3.......9.........22...........46.............86.............148
%C A223815 ..6......50........337.........1922...........9783...........45537
%C A223815 .10.....222.......4120........65465.........921010........11789302
%C A223815 .15.....867......43941......1941904.......76453838......2740448352
%C A223815 .21....3123.....426527.....52310070.....5767953144....581679349302
%C A223815 .28...10660....3875213...1313561156...405333095737.115166445136785
%C A223815 .36...35064...33540705..31302500115.26977674423993
%C A223815 .45..112373..279734339.716436867795
%C A223815 .55..353517.2266708593
%C A223815 .66.1097430
%H A223815 R. H. Hardin, <a href="/A223815/b223815.txt">Table of n, a(n) for n = 1..70</a>
%e A223815 Some solutions for n=3 k=4
%e A223815 ..1..0..1..1....0..1..2..2....0..1..2..1....0..1..0..0....0..1..0..0
%e A223815 ..1..2..1..0....1..2..2..0....2..2..0..0....0..2..1..0....0..1..1..0
%e A223815 ..1..1..2..2....1..1..1..2....0..1..2..2....0..2..1..1....0..0..1..1
%Y A223815 Column 1 is A000217(n+1)
%Y A223815 Column 2 is A222993
%Y A223815 Row 1 is A223718
%K A223815 nonn,tabl
%O A223815 1,1
%A A223815 _R. H. Hardin_ Mar 27 2013