|
%I #4 Dec 15 2017 08:45:18
%S 1,8,37,126,431,1554,5601,20036,71722,256991,920643,3297782,11813230,
%T 42316775,151584446,542999656,1945111540,6967686648,24959322680,
%U 89408160916,320273851760,1147270357089,4109699588023,14721578711022
%N Number of nX4 0..1 arrays with each 1 horizontally, vertically or antidiagonally adjacent to 2 or 4 neighboring 1s.
%C Column 4 of A296541.
%H R. H. Hardin, <a href="/A296537/b296537.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 6*a(n-1) -13*a(n-2) +21*a(n-3) -22*a(n-4) +7*a(n-5) +18*a(n-6) -37*a(n-7) -34*a(n-8) +111*a(n-9) -210*a(n-10) +91*a(n-11) +161*a(n-12) -194*a(n-13) +84*a(n-14) +464*a(n-15) -73*a(n-16) +283*a(n-17) +265*a(n-18) -165*a(n-19) -208*a(n-20) -363*a(n-21) -705*a(n-22) -701*a(n-23) -687*a(n-24) -589*a(n-25) -418*a(n-26) -171*a(n-27) -30*a(n-28) +142*a(n-29) +214*a(n-30) +244*a(n-31) +218*a(n-32) +175*a(n-33) +114*a(n-34) +69*a(n-35) +34*a(n-36) +14*a(n-37) +4*a(n-38) +a(n-39)
%e Some solutions for n=7
%e ..0..0..1..0. .0..1..0..0. .1..1..0..0. .1..1..1..0. .0..1..1..0
%e ..1..1..1..0. .1..1..0..0. .1..0..0..0. .1..1..0..0. .0..1..0..0
%e ..1..0..0..1. .0..0..1..0. .0..1..1..1. .1..0..0..0. .0..0..0..0
%e ..0..0..1..1. .1..1..1..0. .0..1..1..0. .0..1..1..0. .0..0..0..0
%e ..0..0..0..0. .1..0..0..0. .0..1..0..0. .0..1..0..0. .1..1..1..0
%e ..0..0..1..0. .0..1..0..0. .0..0..0..1. .1..1..0..0. .1..1..0..0
%e ..0..1..1..0. .1..1..0..0. .0..0..1..1. .0..0..0..0. .1..0..0..0
%Y Cf. A296541.
%K nonn
%O 1,2
%A _R. H. Hardin_, Dec 15 2017
| 