cp's OEIS Frontend

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.

A208838 Number of nX6 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 1 1 and 1 1 0 vertically.

This page as a plain text file.
%I A208838 #7 Jul 22 2025 21:31:17
%S A208838 26,676,2430,9801,49126,272206,1644265,10399480,67895010,451450105,
%T A208838 3037317426,20579585922,140057351785,955762122172,6533166024022,
%U A208838 44704031815465,306089086744206,2096624267502790,14364797790087081
%N A208838 Number of nX6 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 1 1 and 1 1 0 vertically.
%C A208838 Column 6 of A208840
%H A208838 R. H. Hardin, <a href="/A208838/b208838.txt">Table of n, a(n) for n = 1..210</a>
%F A208838 Empirical: a(n) = 11*a(n-1) -17*a(n-2) -124*a(n-3) +276*a(n-4) +396*a(n-5) -902*a(n-6) -462*a(n-7) +946*a(n-8) +220*a(n-9) -340*a(n-10) -44*a(n-11) +39*a(n-12) +3*a(n-13) -a(n-14) for n>15
%e A208838 Some solutions for n=4
%e A208838 ..0..1..0..1..0..1....0..1..1..1..0..0....0..1..1..1..1..1....1..1..0..1..0..0
%e A208838 ..0..1..0..1..1..0....1..1..1..1..1..1....1..0..1..1..0..0....1..0..1..1..1..1
%e A208838 ..1..1..0..1..0..1....0..1..1..1..0..0....0..1..1..1..1..1....1..1..0..1..0..0
%e A208838 ..0..1..0..1..0..0....0..1..1..1..0..0....1..0..1..1..0..0....1..0..1..1..1..0
%K A208838 nonn
%O A208838 1,1
%A A208838 _R. H. Hardin_ Mar 01 2012