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 A301905 #4 Mar 28 2018 16:08:39 %S A301905 1,10,12,96,320,1934,8781,49709,253844,1413100,7620270,42580016, %T A301905 235818861,1324997099,7432214130,41943560072,236751899580, %U A301905 1339917222874,7587029374109,43012592771281,243943851904936,1384324886282580 %N A301905 Number of nX7 0..1 arrays with every element equal to 0, 2 or 3 horizontally or antidiagonally adjacent elements, with upper left element zero. %C A301905 Column 7 of A301906. %H A301905 R. H. Hardin, <a href="/A301905/b301905.txt">Table of n, a(n) for n = 1..210</a> %F A301905 Empirical: a(n) = 19*a(n-1) -129*a(n-2) +266*a(n-3) +1113*a(n-4) -7787*a(n-5) +16342*a(n-6) +7083*a(n-7) -129016*a(n-8) +332445*a(n-9) -231596*a(n-10) -894953*a(n-11) +2912737*a(n-12) -3222398*a(n-13) -2103447*a(n-14) +12042025*a(n-15) -15194193*a(n-16) -250412*a(n-17) +24253854*a(n-18) -27506576*a(n-19) +1889508*a(n-20) +22587616*a(n-21) -20220872*a(n-22) +2087728*a(n-23) +8489920*a(n-24) -6518528*a(n-25) +1174848*a(n-26) +1096960*a(n-27) -792192*a(n-28) +188672*a(n-29) -9216*a(n-30) for n>33 %e A301905 Some solutions for n=5 %e A301905 ..0..1..1..0..0..0..1. .0..1..1..1..1..1..1. .0..1..1..0..0..0..0 %e A301905 ..1..1..0..0..0..0..0. .1..1..0..1..1..1..0. .1..1..0..0..1..0..0 %e A301905 ..0..1..1..1..1..0..0. .1..1..1..0..0..1..1. .0..1..0..0..1..0..0 %e A301905 ..1..1..0..1..1..0..0. .1..1..0..0..1..1..0. .0..1..0..0..1..0..0 %e A301905 ..1..1..1..1..0..0..1. .1..1..1..1..0..1..0. .0..1..0..0..0..0..1 %Y A301905 Cf. A301906. %K A301905 nonn %O A301905 1,2 %A A301905 _R. H. Hardin_, Mar 28 2018