cp's OEIS Frontend

A219080 Hilltop maps: number of 3 X n binary arrays indicating the locations of corresponding elements not exceeded by any horizontal, diagonal or antidiagonal neighbor in a random 0..1 3 X n array.

%I A219080 #7 Jul 25 2018 05:20:36
%S A219080 1,41,337,2321,17537,134809,1023441,7759553,58921537,447447561,
%T A219080 3397273553,25794057969,195847550081,1487017265657,11290490704977,
%U A219080 85725445999521,650888811968321,4942012485147241,37523285458920273
%N A219080 Hilltop maps: number of 3 X n binary arrays indicating the locations of corresponding elements not exceeded by any horizontal, diagonal or antidiagonal neighbor in a random 0..1 3 X n array.
%C A219080 Row 3 of A219078.
%H A219080 R. H. Hardin, <a href="/A219080/b219080.txt">Table of n, a(n) for n = 1..210</a>
%F A219080 Empirical: a(n) = 6*a(n-1) + 5*a(n-2) + 46*a(n-3) + 61*a(n-4) - 10*a(n-5) - a(n-6) - 10*a(n-7).
%F A219080 Empirical g.f.: x*(1 + 35*x + 86*x^2 + 48*x^3 - 21*x^4 - 11*x^5 - 10*x^6) / (1 - 6*x - 5*x^2 - 46*x^3 - 61*x^4 + 10*x^5 + x^6 + 10*x^7). - _Colin Barker_, Jul 25 2018
%e A219080 Some solutions for n=3:
%e A219080 ..1..1..0....0..1..1....0..1..1....1..1..1....1..1..1....0..1..0....0..1..0
%e A219080 ..0..1..0....0..1..1....1..1..0....1..1..1....0..0..0....0..0..1....1..1..0
%e A219080 ..0..0..1....0..1..0....1..0..0....0..0..1....0..1..1....0..1..1....1..1..1
%Y A219080 Cf. A219078.
%K A219080 nonn
%O A219080 1,2
%A A219080 _R. H. Hardin_, Nov 11 2012