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 A188838 #10 Apr 30 2018 12:24:13 %S A188838 16,55,121,221,364,560,820,1156,1581,2109,2755,3535,4466,5566,6854, %T A188838 8350,10075,12051,14301,16849,19720,22940,26536,30536,34969,39865, %U A188838 45255,51171,57646,64714,72410,80770,89831,99631,110209,121605,133860,147016,161116 %N A188838 Number of n X 4 binary arrays without the pattern 0 1 diagonally or vertically. %C A188838 Column 4 of A188843. %H A188838 R. H. Hardin, <a href="/A188838/b188838.txt">Table of n, a(n) for n = 1..200</a> %F A188838 Empirical: a(n) = (1/24)*n^4 + (11/12)*n^3 + (155/24)*n^2 + (163/12)*n - 6 for n>1. %F A188838 Empirical g.f.: x*(16 - 25*x + 6*x^2 + 6*x^3 - x^4 - x^5) / (1 - x)^5. - _Colin Barker_, Apr 30 2018 %e A188838 Some solutions for 3 X 4: %e A188838 ..1..1..1..1....0..1..0..1....1..1..1..0....1..1..0..0....1..1..0..0 %e A188838 ..0..1..1..1....0..0..0..0....1..1..1..0....1..1..0..0....0..0..0..0 %e A188838 ..0..0..1..1....0..0..0..0....1..1..1..0....1..1..0..0....0..0..0..0 %Y A188838 Cf. A188843. %K A188838 nonn %O A188838 1,1 %A A188838 _R. H. Hardin_, Apr 12 2011