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%I #4 Jul 01 2013 11:41:19
%S 2,4,4,7,15,7,11,48,48,11,16,136,239,136,16,22,341,1084,1084,341,22,
%T 29,771,4444,8427,4444,771,29,37,1606,16366,60039,60039,16366,1606,37,
%U 46,3133,54500,384591,754758,384591,54500,3133,46,56,5789,166271,2209056
%N T(n,k)=Number of nXk 0,1 arrays indicating 2X2 subblocks of some larger (n+1)X(k+1) binary array having a sum of two, with rows and columns of the latter in lexicographically nondecreasing order
%C Table starts
%C ..2....4......7.......11........16.........22.........29..........37.........46
%C ..4...15.....48......136.......341........771.......1606........3133.......5789
%C ..7...48....239.....1084......4444......16366......54500......166271.....470106
%C .11..136...1084.....8427.....60039.....384591....2209056....11456481...54141062
%C .16..341...4444....60039....754758....8638999...89104481...828893716.6983821643
%C .22..771..16366...384591...8638999..180409504.3428152304.58981679762
%C .29.1606..54500..2209056..89104481.3428152304
%C .37.3133.166271.11456481.828893716
%C .46.5789.470106.54141062
%H R. H. Hardin, <a href="/A227103/b227103.txt">Table of n, a(n) for n = 1..84</a>
%F Empirical for column k:
%F k=1: a(n) = (1/2)*n^2 + (1/2)*n + 1
%F k=2: [polynomial of degree 7] for n>3
%F k=3: [polynomial of degree 15] for n>5
%F k=4: [polynomial of degree 31] for n>13
%e Some solutions for n=4 k=4
%e ..0..0..0..0....0..1..0..0....0..1..0..0....0..0..0..1....0..0..0..1
%e ..0..1..0..0....0..1..0..0....1..0..1..0....0..1..1..0....0..0..1..0
%e ..1..0..1..0....0..0..0..0....1..1..1..0....1..1..1..0....0..0..0..0
%e ..1..0..0..1....0..0..0..1....0..1..1..0....0..1..0..0....0..0..1..1
%Y Column 1 is A000124
%K nonn,tabl
%O 1,1
%A _R. H. Hardin_ Jul 01 2013
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