This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A281060 #4 Jan 13 2017 17:01:57 %S A281060 0,122,1492,3416,7803,16875,32370,59669,107693,191953,339219,595824, %T A281060 1041681,1814253,3149435,5451162,9409735,16202663,27835100,47716151, %U A281060 81633286,139397983,237621979,404396106,687167939,1165993033,1975805797 %N A281060 Number of 5Xn 0..1 arrays with no element equal to more than one of its horizontal and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards. %C A281060 Row 5 of A281056. %H A281060 R. H. Hardin, <a href="/A281060/b281060.txt">Table of n, a(n) for n = 1..210</a> %F A281060 Empirical: a(n) = 6*a(n-1) -12*a(n-2) +5*a(n-3) +12*a(n-4) -12*a(n-5) -3*a(n-6) +6*a(n-7) -a(n-9) for n>18 %e A281060 Some solutions for n=4 %e A281060 ..0..1..0..1. .0..0..1..0. .0..1..1..0. .0..0..1..1. .0..1..0..1 %e A281060 ..1..0..1..0. .0..0..1..0. .0..0..1..0. .1..0..0..1. .0..0..0..1 %e A281060 ..1..1..0..1. .1..0..1..0. .1..1..1..1. .1..1..1..0. .1..1..0..1 %e A281060 ..0..1..0..0. .1..0..1..0. .0..1..0..0. .1..0..1..0. .0..1..0..1 %e A281060 ..0..1..1..0. .1..0..1..0. .0..1..1..0. .0..1..0..1. .0..0..1..0 %Y A281060 Cf. A281056. %K A281060 nonn %O A281060 1,2 %A A281060 _R. H. Hardin_, Jan 13 2017