cp's OEIS Frontend

A218898 Number of 2 X n arrays of the minimum value of corresponding elements and their horizontal, diagonal or antidiagonal neighbors in a random 0..1 2 X n array.

%I A218898 #10 Jul 24 2018 20:39:00
%S A218898 4,6,18,34,86,180,426,930,2140,4758,10818,24240,54834,123274,278260,
%T A218898 626446,1412746,3182416,7174106,16164834,36434260,82103270,185041218,
%U A218898 417002816,939796802,2117936730,4773120596,10756848350,24242204506
%N A218898 Number of 2 X n arrays of the minimum value of corresponding elements and their horizontal, diagonal or antidiagonal neighbors in a random 0..1 2 X n array.
%C A218898 Row 2 of A218897.
%H A218898 R. H. Hardin, <a href="/A218898/b218898.txt">Table of n, a(n) for n = 1..210</a>
%F A218898 Empirical: a(n) = a(n-1) + 3*a(n-2) - 2*a(n-5).
%F A218898 Empirical g.f.: 2*x*(2 + x - x^3 - x^4) / (1 - x - 3*x^2 + 2*x^5). - _Colin Barker_, Jul 24 2018
%e A218898 Some solutions for n=3:
%e A218898 ..1..0..1....0..0..1....1..1..1....0..0..1....1..0..0....0..0..0....1..0..0
%e A218898 ..0..0..0....0..0..0....1..1..1....1..0..1....1..0..0....0..0..0....1..0..1
%Y A218898 Cf. A218897.
%K A218898 nonn
%O A218898 1,1
%A A218898 _R. H. Hardin_, Nov 08 2012