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A188448 T(n,k)=Number of (n*k)Xk binary arrays with nonzero rows in decreasing order, no more than 2 ones in any row and exactly n ones in every column.

%I A188448 #9 Jul 22 2025 11:12:50
%S A188448 1,2,0,4,1,0,10,4,0,0,26,18,1,0,0,76,112,10,0,0,0,232,820,112,1,0,0,0,
%T A188448 764,6912,1760,26,0,0,0,0,2620,66178,35150,820,1,0,0,0,0,9496,708256,
%U A188448 848932,35150,76,0,0,0,0,0,35696,8372754,24243520,1944530,6912,1,0,0,0,0
%N A188448 T(n,k)=Number of (n*k)Xk binary arrays with nonzero rows in decreasing order, no more than 2 ones in any row and exactly n ones in every column.
%C A188448 Table starts
%C A188448 .1.2.4.10..26...76...232.....764......2620........9496.........35696
%C A188448 .0.1.4.18.112..820..6912...66178....708256.....8372754.....108306280
%C A188448 .0.0.1.10.112.1760.35150..848932..24243520...805036704...30649435140
%C A188448 .0.0.0..1..26..820.35150.1944530.133948836.11234051976.1127512146540
%C A188448 .0.0.0..0...1...76..6912..848932.133948836.26615510712
%C A188448 .0.0.0..0...0....1...232...66178..24243520
%C A188448 .0.0.0..0...0....0.....1.....764
%C A188448 .0.0.0..0...0....0.....0
%C A188448 .0.0.0..0...0....0
%C A188448 .0.0.0..0...0
%H A188448 R. H. Hardin, <a href="/A188448/b188448.txt">Table of n, a(n) for n = 1..108</a>
%e A188448 All solutions for 9X3
%e A188448 ..1..1..0
%e A188448 ..1..0..1
%e A188448 ..1..0..0
%e A188448 ..0..1..1
%e A188448 ..0..1..0
%e A188448 ..0..0..1
%e A188448 ..0..0..0
%e A188448 ..0..0..0
%e A188448 ..0..0..0
%Y A188448 Row 1 is A000085
%Y A188448 Row 2 is A000986
%Y A188448 Row 3 is A110040
%Y A188448 Row 4 is A139670
%Y A188448 Row 5 is A139671
%Y A188448 Row 6 is A139673
%Y A188448 Row 7 is A139674
%Y A188448 Row 8 is A139675
%K A188448 nonn,tabl
%O A188448 1,2
%A A188448 _R. H. Hardin_ Mar 31 2011