cp's OEIS Frontend

A185407 1/7 the number of nX4 0..6 arrays with every element equal to exactly one or two of its horizontal and vertical neighbors.

%I A185407 #10 Jul 22 2025 09:45:33
%S A185407 7,1848,279918,53808534,9560464068,1755419411964,318289797234978,
%T A185407 58009184105051760,10550717546713596858,1920558372882730002666,
%U A185407 349484670721711744198032,63604421284059206327321532
%N A185407 1/7 the number of nX4 0..6 arrays with every element equal to exactly one or two of its horizontal and vertical neighbors.
%C A185407 Column 4 of A185409
%H A185407 R. H. Hardin, <a href="/A185407/b185407.txt">Table of n, a(n) for n = 1..20</a>
%e A185407 Some solutions for 3X4 with a(1,1)=0
%e A185407 ..0..0..6..6....0..0..0..5....0..0..5..4....0..3..3..1....0..0..0..0
%e A185407 ..3..1..1..1....0..2..3..5....4..3..5..4....0..3..0..1....3..3..3..2
%e A185407 ..3..3..4..4....0..2..3..3....4..3..3..3....0..3..0..0....3..6..6..2
%K A185407 nonn
%O A185407 1,1
%A A185407 _R. H. Hardin_ Jan 26 2011