cp's OEIS Frontend

A218843 Unmatched value maps: number of 2 X n binary arrays indicating the locations of corresponding elements not equal to any horizontal or antidiagonal neighbor in a random 0..1 2 X n array.

%I A218843 #8 Jul 24 2018 20:38:24
%S A218843 1,7,20,57,156,438,1220,3398,9468,26380,73496,204780,570556,1589672,
%T A218843 4429140,12340436,34382820,95797176,266909376,743660900,2071982512,
%U A218843 5772942284,16084528900,44814595084,124862092120,347889834096
%N A218843 Unmatched value maps: number of 2 X n binary arrays indicating the locations of corresponding elements not equal to any horizontal or antidiagonal neighbor in a random 0..1 2 X n array.
%C A218843 Row 2 of A218842.
%H A218843 R. H. Hardin, <a href="/A218843/b218843.txt">Table of n, a(n) for n = 1..210</a>
%F A218843 Empirical: a(n) = 2*a(n-1) + a(n-2) + 3*a(n-3) + 2*a(n-5) + 2*a(n-6) - 2*a(n-7) for n>9.
%F A218843 Empirical g.f.: x*(1 + 5*x + 5*x^2 + 7*x^3 + x^4 + 7*x^5 + x^6 - 2*x^8) / (1 - 2*x - x^2 - 3*x^3 - 2*x^5 - 2*x^6 + 2*x^7). - _Colin Barker_, Jul 24 2018
%e A218843 Some solutions for n=3:
%e A218843 ..0..0..0....0..0..1....1..0..0....1..0..0....1..1..0....0..0..0....0..0..0
%e A218843 ..0..1..1....0..0..1....1..0..1....0..1..1....0..0..0....0..0..1....1..0..0
%Y A218843 Cf. A218842.
%K A218843 nonn
%O A218843 1,2
%A A218843 _R. H. Hardin_, Nov 07 2012