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 A219123 #6 Jul 23 2025 00:14:30 %S A219123 9,87,787,6981,63183,571149,5167013,46755215,423105613,3828940359, %T A219123 34650738731,313579561365,2837811156791,25681442217553, %U A219123 232410308770677,2103252374190595,19033883010223093,172251656124086271 %N A219123 Number of nX3 arrays of the minimum value of corresponding elements and their horizontal, diagonal or antidiagonal neighbors in a random 0..2 nX3 array. %C A219123 Column 3 of A219128 %H A219123 R. H. Hardin, <a href="/A219123/b219123.txt">Table of n, a(n) for n = 1..36</a> %F A219123 Empirical: a(n) = 10*a(n-1) -5*a(n-2) -24*a(n-3) -70*a(n-4) -58*a(n-5) -81*a(n-6) -200*a(n-7) +269*a(n-8) +1056*a(n-9) +1650*a(n-10) +1036*a(n-11) +200*a(n-12) %e A219123 Some solutions for n=3 %e A219123 ..1..0..0....2..1..1....2..0..0....0..0..1....1..1..2....1..0..0....1..1..1 %e A219123 ..2..0..0....2..1..2....0..0..1....2..0..2....1..0..1....2..0..0....1..1..1 %e A219123 ..1..0..1....2..1..1....0..0..2....0..0..1....0..0..2....1..0..2....2..2..2 %K A219123 nonn %O A219123 1,1 %A A219123 _R. H. Hardin_ Nov 12 2012