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A268739 Number of nX7 binary arrays with some 1 horizontally or vertically adjacent to some other 1 exactly once.

%I A268739 #4 Feb 12 2016 08:46:07
%S A268739 38,1183,33170,816009,18847982,418632185,9039552112,191307160577,
%T A268739 3985770068310,82030747371058,1671509767296774,33781019022038039,
%U A268739 678004335124666334,13528033902348727292,268553181861956273470
%N A268739 Number of nX7 binary arrays with some 1 horizontally or vertically adjacent to some other 1 exactly once.
%C A268739 Column 7 of A268740.
%H A268739 R. H. Hardin, <a href="/A268739/b268739.txt">Table of n, a(n) for n = 1..210</a>
%F A268739 Empirical: a(n) = 18*a(n-1) +325*a(n-2) -4074*a(n-3) -48747*a(n-4) +201072*a(n-5) +2225020*a(n-6) -6248320*a(n-7) -47573325*a(n-8) +135873052*a(n-9) +512366407*a(n-10) -1794441336*a(n-11) -2517416282*a(n-12) +13453431136*a(n-13) +1270823811*a(n-14) -55187301646*a(n-15) +38695555999*a(n-16) +115237077158*a(n-17) -158181613013*a(n-18) -96178246900*a(n-19) +263575852534*a(n-20) -18739881048*a(n-21) -224653932202*a(n-22) +90835575680*a(n-23) +105290165907*a(n-24) -69076575582*a(n-25) -27720217521*a(n-26) +26811874806*a(n-27) +3877126783*a(n-28) -6197138172*a(n-29) -207452034*a(n-30) +895782500*a(n-31) -10034133*a(n-32) -81777708*a(n-33) +1520627*a(n-34) +4630616*a(n-35) -28132*a(n-36) -153828*a(n-37) -2195*a(n-38) +2658*a(n-39) +93*a(n-40) -18*a(n-41) -a(n-42)
%e A268739 Some solutions for n=3
%e A268739 ..0..1..0..1..0..0..0. .1..0..0..0..0..1..1. .1..0..1..0..0..0..0
%e A268739 ..0..0..0..0..0..1..0. .0..0..0..1..0..0..0. .0..1..0..1..1..0..1
%e A268739 ..0..0..0..0..0..1..0. .1..0..0..0..1..0..0. .1..0..0..0..0..1..0
%Y A268739 Cf. A268740.
%K A268739 nonn
%O A268739 1,1
%A A268739 _R. H. Hardin_, Feb 12 2016