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Array read by antidiagonals: T(n,k) = number of n X k binary matrices with no initial bit string in any row or column divisible by 4.
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%I #10 Jun 06 2017 17:35:19

%S 1,1,1,1,2,1,1,3,3,1,1,5,7,5,1,1,8,17,17,8,1,1,13,41,63,41,13,1,1,21,

%T 99,227,227,99,21,1,1,34,239,827,1234,827,239,34,1,1,55,577,2999,6743,

%U 6743,2999,577,55,1,1,89,1393,10897,36787,55447,36787,10897,1393,89,1,1,144

%N Array read by antidiagonals: T(n,k) = number of n X k binary matrices with no initial bit string in any row or column divisible by 4.

%C A089980 is essentially the same array (see the Comments by _Steve Butler_ in A006506). - _N. J. A. Sloane_, Jan 27 2015

%H R. H. Hardin, <a href="/A181031/b181031.txt">Table of n, a(n) for n=1..1057</a>

%e Table starts

%e .1..1....1......1.......1.........1...........1............1..............1

%e .1..2....3......5.......8........13..........21...........34.............55

%e .1..3....7.....17......41........99.........239..........577...........1393

%e .1..5...17.....63.....227.......827........2999........10897..........39561

%e .1..8...41....227....1234......6743.......36787.......200798........1095851

%e .1.13...99....827....6743.....55447......454385......3729091.......30584687

%e .1.21..239...2999...36787....454385.....5598861.....69050253......851302029

%e .1.34..577..10897..200798...3729091....69050253...1280128950....23720149995

%e .1.55.1393..39561.1095851..30584687...851302029..23720149995...660647962955

%e .1.89.3363.143677.5980913.250916131.10496827403.439621976195.18403310404291

%e Some solutions for 5X5

%e ..1..1..1..1..1....1..1..1..1..1....1..1..1..1..1....1..1..1..1..1

%e ..1..0..1..0..1....1..0..1..0..1....1..0..1..0..1....1..0..1..0..1

%e ..1..1..0..1..0....1..1..0..1..0....1..1..0..1..0....1..1..0..1..0

%e ..1..0..1..0..1....1..0..1..0..1....1..0..1..0..1....1..0..1..0..1

%e ..1..1..0..1..0....1..1..0..1..1....1..1..1..1..0....1..1..1..1..1

%Y Cf. A089980.

%K nonn,tabl

%O 1,5

%A _R. H. Hardin_, Sep 30 2010