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 A189261 #7 Jul 22 2025 11:38:42 %S A189261 33,1089,18960,308266,4628486,68635317,1010709182,14861981162, %T A189261 218354201468,3207581304325,47115298896367,692052648696687, %U A189261 10165129114423772,149309006382444045,2193102055504811375 %N A189261 Number of nX6 binary arrays without the pattern 0 0 1 diagonally, antidiagonally or horizontally. %C A189261 Column 6 of A189264 %H A189261 R. H. Hardin, <a href="/A189261/b189261.txt">Table of n, a(n) for n = 1..200</a> %F A189261 Empirical: a(n) = 22*a(n-1) -94*a(n-2) -284*a(n-3) +1733*a(n-4) -11352*a(n-5) +67835*a(n-6) +76752*a(n-7) -853449*a(n-8) +901976*a(n-9) -5740086*a(n-10) +13739028*a(n-11) +44197303*a(n-12) +124759854*a(n-13) -1024073157*a(n-14) -2525205604*a(n-15) +14327510563*a(n-16) +712547050*a(n-17) -47952956322*a(n-18) +31323634540*a(n-19) -35406686682*a(n-20) +88990999576*a(n-21) +188444788988*a(n-22) -331486365542*a(n-23) -11633051789*a(n-24) -703000156294*a(n-25) +1085177784618*a(n-26) +1458830130414*a(n-27) -1766461853158*a(n-28) -476544246624*a(n-29) -234644319566*a(n-30) -2144529292192*a(n-31) +5969478396944*a(n-32) +1184010556568*a(n-33) -8359720474800*a(n-34) +1973474480880*a(n-35) +3293959223808*a(n-36) -249942799712*a(n-37) -608152874432*a(n-38) -947744263232*a(n-39) +572978394752*a(n-40) +131230520064*a(n-41) -58568504448*a(n-42) -12940005888*a(n-43) -838978560*a(n-44) for n>47 %e A189261 Some solutions for 6X3 %e A189261 ..1..0..0....1..1..0....1..0..0....0..1..1....0..0..1....0..0..1....1..0..1 %e A189261 ..0..1..1....1..1..0....1..1..1....1..1..1....1..1..1....1..1..1....0..0..0 %e A189261 ..1..0..1....1..1..0....1..1..0....1..1..1....0..1..0....0..0..0....1..0..0 %e A189261 ..1..1..0....1..1..0....1..0..1....1..1..0....1..1..0....1..1..0....0..0..0 %e A189261 ..0..1..0....0..1..0....0..0..1....0..0..0....0..0..0....1..1..0....0..0..0 %e A189261 ..1..0..0....0..1..0....1..0..1....0..1..0....0..0..0....0..1..0....0..0..0 %K A189261 nonn %O A189261 1,1 %A A189261 _R. H. Hardin_ Apr 19 2011