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 A249461 #7 Jul 23 2025 12:01:00 %S A249461 860,2948,10124,34832,119932,412972,1422232,4898776,16874830,58131580, %T A249461 200257200,689871586,2376578686,8187255382,28204984386,97165888404, %U A249461 334735779168,1153163060226,3972642458048,13685741942400,47147347303294 %N A249461 Number of length n+4 0..3 arrays with no five consecutive terms having four times any element equal to the sum of the remaining four. %C A249461 Column 3 of A249466 %H A249461 R. H. Hardin, <a href="/A249461/b249461.txt">Table of n, a(n) for n = 1..210</a> %e A249461 Some solutions for n=5 %e A249461 ..1....3....2....0....3....2....2....3....0....0....2....0....3....1....1....2 %e A249461 ..3....0....1....0....3....3....0....2....3....3....0....2....0....2....2....3 %e A249461 ..0....0....0....0....2....1....0....0....0....0....2....2....2....3....1....3 %e A249461 ..0....0....3....2....0....2....1....0....3....2....3....0....0....1....2....3 %e A249461 ..2....0....2....0....3....1....1....0....1....1....2....2....0....2....0....2 %e A249461 ..2....2....2....1....3....0....2....2....3....1....0....2....1....3....3....0 %e A249461 ..2....2....1....3....3....3....2....3....2....3....1....0....3....0....1....0 %e A249461 ..3....3....3....3....2....0....3....0....0....0....3....3....3....3....2....1 %e A249461 ..3....1....1....2....3....3....1....0....0....3....1....1....2....0....0....3 %K A249461 nonn %O A249461 1,1 %A A249461 _R. H. Hardin_, Oct 29 2014