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A232072 Number of (n+1)X(4+1) 0..1 arrays with every element equal to some horizontal, diagonal or antidiagonal neighbor, with top left element zero.

%I A232072 #6 Jul 23 2025 06:51:48
%S A232072 161,3681,91636,2265691,56126173,1389867384,34420057373,852404560481,
%T A232072 21109624812630,522775448585677,12946425187404245,320615523780601420,
%U A232072 7939976687329054275,196631869363448682249,4869547301285168517052
%N A232072 Number of (n+1)X(4+1) 0..1 arrays with every element equal to some horizontal, diagonal or antidiagonal neighbor, with top left element zero.
%C A232072 Column 4 of A232076
%H A232072 R. H. Hardin, <a href="/A232072/b232072.txt">Table of n, a(n) for n = 1..210</a>
%F A232072 Empirical: a(n) = 18*a(n-1) +162*a(n-2) +236*a(n-3) -2046*a(n-4) -9966*a(n-5) -6228*a(n-6) +65257*a(n-7) +188276*a(n-8) -46843*a(n-9) -649584*a(n-10) -764788*a(n-11) +412637*a(n-12) +1321769*a(n-13) +761732*a(n-14) +182925*a(n-15) -381900*a(n-16) -337601*a(n-17) -102296*a(n-18) +5318*a(n-19) -23355*a(n-20) -10567*a(n-21) -20176*a(n-22) -133*a(n-23) -430*a(n-24) -2201*a(n-25) +428*a(n-26) +116*a(n-27) +62*a(n-28) +8*a(n-29) +4*a(n-30)
%e A232072 Some solutions for n=3
%e A232072 ..0..1..1..1..1....0..0..0..1..0....0..0..1..1..1....0..0..0..1..0
%e A232072 ..0..0..0..1..0....1..0..1..0..1....1..1..0..0..1....1..1..1..0..0
%e A232072 ..0..0..1..0..1....0..1..0..1..1....1..1..0..1..1....0..0..0..1..0
%e A232072 ..0..0..0..1..0....0..0..1..0..1....1..0..0..0..0....0..0..0..1..1
%K A232072 nonn
%O A232072 1,1
%A A232072 _R. H. Hardin_, Nov 17 2013