cp's OEIS Frontend

A297221 Number of n X 5 0..1 arrays with every 1 horizontally or antidiagonally adjacent to 1 neighboring 1s.

%I A297221 #8 Feb 26 2019 12:05:54
%S A297221 6,33,182,997,5570,30946,171851,955316,5308160,29497088,163916530,
%T A297221 910869797,5061672943,28127490455,156303166524,868569845751,
%U A297221 4826603668246,26821221189069,149044329620412,828232684722634
%N A297221 Number of n X 5 0..1 arrays with every 1 horizontally or antidiagonally adjacent to 1 neighboring 1s.
%H A297221 R. H. Hardin, <a href="/A297221/b297221.txt">Table of n, a(n) for n = 1..210</a>
%F A297221 Empirical: a(n) = a(n-1) + 16*a(n-2) + 45*a(n-3) + 39*a(n-4) - 3*a(n-5) - 21*a(n-6) + 8*a(n-7) - 4*a(n-8) + a(n-9).
%F A297221 Empirical g.f.: x*(6 + 27*x + 53*x^2 + 17*x^3 - 58*x^4 - 35*x^5 + 47*x^6 - 13*x^7 + x^8) / ((1 + 2*x + x^2 - x^3)*(1 - 3*x - 11*x^2 - 19*x^3 + 7*x^4 - 3*x^5 + x^6)). - _Colin Barker_, Feb 26 2019
%e A297221 Some solutions for n=7:
%e A297221 ..0..0..0..0..0. .0..0..0..1..1. .0..0..0..1..1. .0..0..0..0..0
%e A297221 ..0..0..0..1..1. .0..1..0..0..1. .1..1..0..0..0. .1..1..0..0..0
%e A297221 ..0..0..0..0..1. .1..0..0..1..0. .0..0..1..1..0. .0..0..0..1..1
%e A297221 ..0..0..0..1..0. .0..0..0..0..0. .0..0..0..0..1. .0..0..0..0..0
%e A297221 ..0..0..0..0..0. .0..0..1..1..0. .0..1..0..1..0. .1..1..0..1..0
%e A297221 ..0..0..1..0..0. .0..0..0..0..0. .1..0..0..0..0. .0..0..1..0..0
%e A297221 ..0..1..0..1..1. .0..0..1..1..0. .0..0..1..1..0. .0..0..1..1..0
%Y A297221 Column 5 of A297224.
%K A297221 nonn
%O A297221 1,1
%A A297221 _R. H. Hardin_, Dec 27 2017