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 A188609 #7 Feb 22 2025 18:55:34 %S A188609 12,144,883,4914,26723,140617,721597,3648942,18246880,90587254, %T A188609 447352515,2201344823,10804697625,52937908893,259040875255, %U A188609 1266429871446,6187499700062,30216983863723,147517894395275,720006607430081 %N A188609 Number of 4 X n binary arrays without the pattern 1 1 0 diagonally, vertically, antidiagonally or horizontally. %C A188609 Row 4 of A188607. %H A188609 R. H. Hardin, <a href="/A188609/b188609.txt">Table of n, a(n) for n = 1..200</a> %F A188609 Empirical: a(n) = 7*a(n-1) + 21*a(n-2) - 204*a(n-3) - 173*a(n-4) + 2511*a(n-5) + 968*a(n-6) - 16924*a(n-7) - 7305*a(n-8) + 66761*a(n-9) + 54645*a(n-10) - 143677*a(n-11) - 256857*a(n-12) + 68263*a(n-13) + 687548*a(n-14) + 523337*a(n-15) - 912372*a(n-16) - 1629031*a(n-17) + 15630*a(n-18) + 2223883*a(n-19) + 1882654*a(n-20) - 1146529*a(n-21) - 2882783*a(n-22) - 899121*a(n-23) + 1832939*a(n-24) + 1848965*a(n-25) - 159860*a(n-26) - 1209333*a(n-27) - 505167*a(n-28) + 332928*a(n-29) + 341728*a(n-30) - 17599*a(n-31) - 115526*a(n-32) - 10956*a(n-33) + 28972*a(n-34) + 12641*a(n-35) - 5903*a(n-36) - 6775*a(n-37) + 1312*a(n-38) + 688*a(n-39) - 554*a(n-40) + 201*a(n-41) + 84*a(n-42) - 36*a(n-43) for n>46. %e A188609 Some solutions for 4 X 3 %e A188609 ..0..0..0....0..1..0....1..0..1....0..0..1....1..1..1....0..1..1....1..0..0 %e A188609 ..1..0..0....0..1..0....0..0..0....0..0..1....0..0..1....1..0..0....0..1..0 %e A188609 ..0..0..1....0..1..0....1..1..1....0..0..1....0..0..1....1..0..0....0..0..1 %e A188609 ..0..1..1....1..1..1....0..0..0....0..1..1....1..0..1....1..0..1....1..0..0 %Y A188609 Cf. A188607. %K A188609 nonn %O A188609 1,1 %A A188609 _R. H. Hardin_, Apr 05 2011