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.

A184201 Number of (n+1)X4 binary arrays with no 2X2 subblock containing fewer than two 1s.

This page as a plain text file.
%I A184201 #7 Jul 22 2025 09:29:42
%S A184201 108,1028,8969,80812,721939,6468501,57909336,518574936,4643443850,
%T A184201 41579555979,372319892218,3333908362279,29853191601007,
%U A184201 267317859115808,2393674819332654,21433956109836050,191928522580951331
%N A184201 Number of (n+1)X4 binary arrays with no 2X2 subblock containing fewer than two 1s.
%C A184201 Column 3 of A184207
%H A184201 R. H. Hardin, <a href="/A184201/b184201.txt">Table of n, a(n) for n = 1..200</a>
%F A184201 Empirical: a(n)=9*a(n-1)+8*a(n-2)-79*a(n-3)+19*a(n-4)+134*a(n-5)-54*a(n-6)-56*a(n-7)+23*a(n-8)+5*a(n-9)-2*a(n-10)
%e A184201 Some solutions for 3X4
%e A184201 ..1..1..1..1....0..0..1..1....0..1..0..1....1..0..0..1....0..1..0..1
%e A184201 ..0..1..1..0....1..1..1..1....1..1..1..1....0..1..1..1....1..1..1..0
%e A184201 ..1..1..1..1....1..0..0..1....0..0..0..0....1..1..1..1....0..0..1..1
%K A184201 nonn
%O A184201 1,1
%A A184201 _R. H. Hardin_ Jan 10 2011