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%I #7 Sep 08 2013 03:09:59
%S 64,233,12444,135768,3459357,53992646,1104367784,19393508581,
%T 370265354930,6753498762208,126219807740277,2328950576310612,
%U 43257528262721468,800768205769855817,14848408425344987460
%N Number of 7Xn binary arrays with top left element equal to 1 and no two ones adjacent horizontally or nw-se.
%C Row 7 of A228796
%H R. H. Hardin, <a href="/A228802/b228802.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = a(n-1) +288*a(n-2) +1417*a(n-3) -11199*a(n-4) -59098*a(n-5) +236338*a(n-6) +948288*a(n-7) -3278724*a(n-8) -6872522*a(n-9) +27696998*a(n-10) +17458752*a(n-11) -128873759*a(n-12) +35614933*a(n-13) +298960774*a(n-14) -258487597*a(n-15) -292412017*a(n-16) +426432960*a(n-17) +93229829*a(n-18) -323469437*a(n-19) +28233040*a(n-20) +135906279*a(n-21) -29253017*a(n-22) -34819910*a(n-23) +8867758*a(n-24) +5748836*a(n-25) -1311708*a(n-26) -619302*a(n-27) +94650*a(n-28) +41064*a(n-29) -2481*a(n-30) -1413*a(n-31) -22*a(n-32) +17*a(n-33) +a(n-34)
%e Some solutions for n=4
%e ..1..0..0..0....1..0..0..0....1..0..0..1....1..0..0..1....1..0..0..1
%e ..0..0..0..0....0..0..1..0....0..0..1..0....0..0..0..0....0..0..1..0
%e ..0..1..0..1....0..1..0..0....0..1..0..0....0..0..0..0....0..0..0..0
%e ..0..0..0..0....1..0..0..1....0..1..0..0....0..0..0..0....0..1..0..1
%e ..0..0..0..1....0..0..1..0....0..0..0..0....1..0..0..0....1..0..0..0
%e ..0..1..0..1....0..0..0..0....0..1..0..0....0..0..0..1....1..0..0..0
%e ..0..0..0..0....0..1..0..0....0..0..0..0....0..0..1..0....0..0..1..0
%K nonn
%O 1,1
%A _R. H. Hardin_ Sep 04 2013
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