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 A280066 #4 Dec 25 2016 06:39:10 %S A280066 3,9,39,170,790,3729,17468,82769,394904,1890877,9080800,43650638, %T A280066 210047292,1011165147,4869719373,23456281889,113000007399, %U A280066 544411868911,2623011742357,12638188505237,60894518951302,293410920660702 %N A280066 Number of nX5 0..1 arrays with no element unequal to a strict majority of its horizontal, vertical and antidiagonal neighbors and with new values introduced in order 0 sequentially upwards. %C A280066 Column 5 of A280069. %H A280066 R. H. Hardin, <a href="/A280066/b280066.txt">Table of n, a(n) for n = 1..210</a> %F A280066 Empirical: a(n) = 8*a(n-1) -4*a(n-2) -97*a(n-3) +176*a(n-4) +339*a(n-5) -1073*a(n-6) -47*a(n-7) +3377*a(n-8) -3342*a(n-9) -7621*a(n-10) +13813*a(n-11) +10465*a(n-12) -31408*a(n-13) -5811*a(n-14) +90585*a(n-15) -69504*a(n-16) -167596*a(n-17) +292370*a(n-18) -85078*a(n-19) -228536*a(n-20) +394124*a(n-21) -113838*a(n-22) -192578*a(n-23) +250274*a(n-24) -199426*a(n-25) -58314*a(n-26) +185492*a(n-27) -136476*a(n-28) +48376*a(n-29) +64368*a(n-30) -69640*a(n-31) +27472*a(n-32) +2400*a(n-33) -15956*a(n-34) +6480*a(n-35) for n>40 %e A280066 Some solutions for n=4 %e A280066 ..0..1..1..1..1. .0..0..0..0..0. .0..1..1..0..0. .0..0..1..1..1 %e A280066 ..0..1..1..1..1. .1..1..0..0..0. .0..1..1..0..0. .0..0..1..1..0 %e A280066 ..0..0..1..1..0. .1..1..0..0..0. .0..0..1..1..1. .0..0..0..0..0 %e A280066 ..0..0..1..0..0. .1..1..1..1..1. .0..0..1..1..1. .0..0..0..0..0 %Y A280066 Cf. A280069. %K A280066 nonn %O A280066 1,1 %A A280066 _R. H. Hardin_, Dec 25 2016