cp's OEIS Frontend

A217978 Number of n X 4 arrays of the minimum value of corresponding elements and their horizontal, vertical, diagonal or antidiagonal neighbors in a random 0..1 n X 4 array.

%I A217978 #7 Jul 23 2018 15:46:17
%S A217978 6,6,36,98,362,1180,4046,13594,46052,155494,525730,1776548,6004634,
%T A217978 20293538,68587432,231806206,783444274,2647830256,8948960354,
%U A217978 30245088582,102220312680,345477304222,1167620873294,3946246173440,13337256366382
%N A217978 Number of n X 4 arrays of the minimum value of corresponding elements and their horizontal, vertical, diagonal or antidiagonal neighbors in a random 0..1 n X 4 array.
%C A217978 Column 4 of A217982.
%H A217978 R. H. Hardin, <a href="/A217978/b217978.txt">Table of n, a(n) for n = 1..210</a>
%F A217978 Empirical: a(n) = 2*a(n-1) + 5*a(n-2) + a(n-3) - 5*a(n-4) - 8*a(n-5) + a(n-6) + 2*a(n-7).
%F A217978 Empirical g.f.: 2*x*(3 - 3*x - 3*x^2 - 5*x^3 + 5*x^4 + 4*x^5) / (1 - 2*x - 5*x^2 - x^3 + 5*x^4 + 8*x^5 - x^6 - 2*x^7). - _Colin Barker_, Jul 23 2018
%e A217978 Some solutions for n=3:
%e A217978 ..1..1..0..0....0..0..0..1....1..1..1..1....0..0..1..1....1..0..0..0
%e A217978 ..0..0..0..0....0..0..0..0....0..0..0..1....0..0..0..0....0..0..0..0
%e A217978 ..0..0..1..1....1..0..0..0....0..0..0..1....1..0..0..0....0..0..0..0
%Y A217978 Cf. A217982.
%K A217978 nonn
%O A217978 1,1
%A A217978 _R. H. Hardin_, Oct 16 2012