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 A188875 #7 Jul 22 2025 11:26:51 %S A188875 8,64,316,1901,11332,65656,385700,2262261,13249261,77665756,455194656, %T A188875 2667688716,15634970127,91633239536,537041598796,3147488927460, %U A188875 18446758005813,108112489924349,633624215112740,3713535944800748 %N A188875 Number of 3Xn binary arrays without the pattern 0 0 0 antidiagonally or horizontally. %C A188875 Row 3 of A188874 %H A188875 R. H. Hardin, <a href="/A188875/b188875.txt">Table of n, a(n) for n = 1..200</a> %F A188875 Empirical: a(n) = 3*a(n-1) +10*a(n-2) +41*a(n-3) -3*a(n-4) -10*a(n-5) -124*a(n-6) +96*a(n-7) -50*a(n-8) +71*a(n-9) -43*a(n-10) +14*a(n-11) -5*a(n-12) +a(n-13) %e A188875 Some solutions for 3X3 %e A188875 ..1..1..0....1..1..1....0..1..1....1..1..1....0..1..1....0..1..1....0..0..1 %e A188875 ..1..0..0....1..0..0....1..0..0....1..0..1....0..1..1....1..1..1....0..1..0 %e A188875 ..1..1..0....1..1..1....1..0..1....0..0..1....1..1..0....1..1..1....1..0..1 %K A188875 nonn %O A188875 1,1 %A A188875 _R. H. Hardin_ Apr 12 2011