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 A218060 #7 Jul 23 2018 15:02:23 %S A218060 6,42,260,1664,10566,66978,424332,2687866,17025060,107835994, %T A218060 683025864,4326234664,27402037744,173562384900,1099330676692, %U A218060 6963075143418,44103577188722,279348632561274,1769372542444278,11207068261293544 %N A218060 Number of n X 4 arrays of the minimum value of corresponding elements and their horizontal or antidiagonal neighbors in a random 0..1 n X 4 array. %C A218060 Column 4 of A218064. %H A218060 R. H. Hardin, <a href="/A218060/b218060.txt">Table of n, a(n) for n = 1..210</a> %F A218060 Empirical: a(n) = 9*a(n-1) - 18*a(n-2) + 6*a(n-3) + 7*a(n-4) - 2*a(n-5) - a(n-6) for n>7. %F A218060 Empirical g.f.: 2*x*(3 - 6*x - 5*x^2 + 22*x^3 - 12*x^4 - 3*x^5 + 2*x^6) / ((1 - x)*(1 - 8*x + 10*x^2 + 4*x^3 - 3*x^4 - x^5)). - _Colin Barker_, Jul 23 2018 %e A218060 Some solutions for n=3: %e A218060 ..0..0..1..1....1..1..0..0....0..0..1..1....1..0..0..0....0..0..1..1 %e A218060 ..0..0..1..1....1..0..0..0....0..0..0..0....0..0..1..1....0..0..1..1 %e A218060 ..1..1..0..0....0..0..0..1....1..1..0..1....1..1..1..1....0..0..1..1 %Y A218060 Cf. A218064. %K A218060 nonn %O A218060 1,1 %A A218060 _R. H. Hardin_, Oct 19 2012