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 A300772 #4 Mar 12 2018 11:26:20 %S A300772 0,4,11,36,179,735,3482,15986,74347,346927,1617399,7555603,35285141, %T A300772 164831052,770046798,3597506545,16807267889,78522710349,366856173460, %U A300772 1713946215073,8007540142806,37411176619541,174784828107456 %N A300772 Number of nX4 0..1 arrays with every element equal to 2, 3, 4 or 6 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero. %C A300772 Column 4 of A300776. %H A300772 R. H. Hardin, <a href="/A300772/b300772.txt">Table of n, a(n) for n = 1..210</a> %F A300772 Empirical: a(n) = 7*a(n-1) -9*a(n-2) -8*a(n-3) -4*a(n-4) -15*a(n-5) +109*a(n-6) -99*a(n-7) -458*a(n-8) +1125*a(n-9) +451*a(n-10) -583*a(n-11) +9930*a(n-12) -11717*a(n-13) -15608*a(n-14) +35687*a(n-15) -58043*a(n-16) -57980*a(n-17) +158871*a(n-18) -117558*a(n-19) -9006*a(n-20) +323563*a(n-21) -373476*a(n-22) +364769*a(n-23) -111053*a(n-24) -347366*a(n-25) +535625*a(n-26) -584685*a(n-27) +219534*a(n-28) +20570*a(n-29) -57144*a(n-30) +264924*a(n-31) -292999*a(n-32) +55855*a(n-33) -39233*a(n-34) +197186*a(n-35) -87979*a(n-36) -47711*a(n-37) -8147*a(n-38) +8342*a(n-39) +30624*a(n-40) +6927*a(n-41) -55515*a(n-42) +52943*a(n-43) -29970*a(n-44) +20894*a(n-45) -13250*a(n-46) +3727*a(n-47) -777*a(n-48) +1639*a(n-49) -1592*a(n-50) +674*a(n-51) -130*a(n-52) +20*a(n-53) -13*a(n-54) +6*a(n-55) -a(n-56) for n>57 %e A300772 Some solutions for n=5 %e A300772 ..0..0..0..0. .0..0..0..1. .0..0..0..1. .0..0..0..0. .0..0..0..1 %e A300772 ..0..0..1..0. .0..0..1..1. .0..0..1..1. .0..1..1..0. .0..0..1..1 %e A300772 ..0..1..1..0. .0..1..0..0. .1..1..0..0. .0..1..0..0. .0..1..1..1 %e A300772 ..1..1..0..0. .1..1..0..1. .1..0..0..1. .0..0..1..1. .0..0..0..0 %e A300772 ..1..0..0..0. .1..1..1..1. .0..0..1..1. .0..1..1..1. .0..0..0..0 %Y A300772 Cf. A300776. %K A300772 nonn %O A300772 1,2 %A A300772 _R. H. Hardin_, Mar 12 2018