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%I #4 Sep 17 2015 22:20:56
%S 5,9,17,133,361,1009,8357,33993,127121,795013,3876585,16907121,
%T 90644645,463649609,2179845009,11046180229,56646588009,276046895345,
%U 1376462436005,7003379302345,34679915634321,172507268999557,871215356444137
%N Number of (n+2)X(3+2) 0..1 arrays with each row and column divisible by 7, read as a binary number with top and left being the most significant bits.
%C Column 3 of A262319.
%H R. H. Hardin, <a href="/A262315/b262315.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 5*a(n-1) +203*a(n-3) -1015*a(n-4) -17262*a(n-6) +86310*a(n-7) +803306*a(n-9) -4016530*a(n-10) -22920723*a(n-12) +114603615*a(n-13) +424713065*a(n-15) -2123565325*a(n-16) -5289109868*a(n-18) +26445549340*a(n-19) +45727616604*a(n-21) -228638083020*a(n-22) -289788580823*a(n-24) +1448942904115*a(n-25) +1453125527917*a(n-27) -7265627639585*a(n-28) -5836364956590*a(n-30) +29181824782950*a(n-31) +16212555187738*a(n-33) -81062775938690*a(n-34) -21276199455861*a(n-36) +106380997279305*a(n-37) -6355957095425*a(n-39) +31779785477125*a(n-40) +38763541794536*a(n-42) -193817708972680*a(n-43)
%e Some solutions for n=4
%e ..0..0..1..1..1....1..1..1..0..0....0..1..1..1..0....1..1..1..0..0
%e ..0..0..1..1..1....1..0..1..0..1....1..0..1..0..1....1..0..1..0..1
%e ..0..0..1..1..1....0..0..1..1..1....1..0..1..0..1....1..0..1..0..1
%e ..0..0..1..1..1....0..0..1..1..1....1..0..1..0..1....0..0..1..1..1
%e ..0..0..1..1..1....0..1..1..1..0....0..1..1..1..0....0..1..1..1..0
%e ..0..0..1..1..1....1..1..1..0..0....0..1..1..1..0....0..1..1..1..0
%Y Cf. A262319.
%K nonn
%O 1,1
%A _R. H. Hardin_, Sep 17 2015
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