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Number of nX7 binary arrays with some element plus some horizontally, diagonally or antidiagonally adjacent neighbor totalling two not more than once.
1

%I #4 Feb 19 2016 08:43:58

%S 72,1204,27042,542112,10778640,210476400,4064720816,77785162880,

%T 1477636398784,27897108860960,523921783242624,9794822341611072,

%U 182387895832407680,3384281324193062016,62600172035227164032

%N Number of nX7 binary arrays with some element plus some horizontally, diagonally or antidiagonally adjacent neighbor totalling two not more than once.

%C Column 7 of A269075.

%H R. H. Hardin, <a href="/A269074/b269074.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 60*a(n-1) -1352*a(n-2) +13344*a(n-3) -35948*a(n-4) -311480*a(n-5) +1985472*a(n-6) +1821840*a(n-7) -31021776*a(n-8) +4125984*a(n-9) +251967152*a(n-10) -46853056*a(n-11) -1173410880*a(n-12) -138650624*a(n-13) +2912101888*a(n-14) +1295316992*a(n-15) -3360870400*a(n-16) -2339016704*a(n-17) +1368141824*a(n-18) +1168457728*a(n-19) -291553280*a(n-20) -245170176*a(n-21) +45023232*a(n-22) +19922944*a(n-23) -4194304*a(n-24) for n>25

%e Some solutions for n=3

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

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

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

%Y Cf. A269075.

%K nonn

%O 1,1

%A _R. H. Hardin_, Feb 19 2016