cp's OEIS Frontend

A218892 Number of n X 3 arrays of the minimum value of corresponding elements and their horizontal, diagonal or antidiagonal neighbors in a random 0..1 n X 3 array.

%I A218892 #8 Jul 24 2018 20:38:35
%S A218892 4,18,72,286,1162,4700,19046,77198,312944,1268694,5143506,20852924,
%T A218892 84542894,342758566,1389632608,5633935678,22841460250,92605309212,
%U A218892 375446383830,1522158836638,6171234143440,25019814013190,101436937848962
%N A218892 Number of n X 3 arrays of the minimum value of corresponding elements and their horizontal, diagonal or antidiagonal neighbors in a random 0..1 n X 3 array.
%C A218892 Column 3 of A218897.
%H A218892 R. H. Hardin, <a href="/A218892/b218892.txt">Table of n, a(n) for n = 1..210</a>
%F A218892 Empirical: a(n) = 4*a(n-1) + 2*a(n-2) - 5*a(n-3) - 8*a(n-4) - 4*a(n-5).
%F A218892 Empirical g.f.: 2*x*(2 + x - 4*x^2 - 9*x^3 - 2*x^4) / (1 - 4*x - 2*x^2 + 5*x^3 + 8*x^4 + 4*x^5). - _Colin Barker_, Jul 24 2018
%e A218892 Some solutions for n=3:
%e A218892 ..0..0..1....1..0..1....0..0..0....0..0..0....0..0..1....0..0..0....0..0..1
%e A218892 ..1..0..1....0..0..0....0..0..0....1..0..0....0..0..1....0..0..0....1..0..0
%e A218892 ..0..0..0....1..0..0....0..0..0....1..0..1....1..0..1....1..0..1....1..0..0
%Y A218892 Cf. A218897.
%K A218892 nonn
%O A218892 1,1
%A A218892 _R. H. Hardin_, Nov 08 2012