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 A251804 #6 Jun 02 2025 10:32:38 %S A251804 216912,18577404,873945739,26787273856,594938582014,10280556043804, %T A251804 145329837643171,1743692215971208,18257820090771490, %U A251804 170475350875241504,1443843489205389919,11245777833263175252,81459269805049215890 %N A251804 Number of (4+1)X(n+1) 0..3 arrays with no 2X2 subblock having x11-x00 less than x10-x01. %C A251804 Row 4 of A251801 %H A251804 R. H. Hardin, <a href="/A251804/b251804.txt">Table of n, a(n) for n = 1..210</a> %H A251804 R. H. Hardin, <a href="/A251804/a251804.txt">Empirical recurrence of order 52</a> %F A251804 Empirical recurrence of order 52 (see link above) %e A251804 Some solutions for n=1 %e A251804 ..0..0....0..1....0..2....2..2....2..2....2..3....0..2....0..3....0..2....0..2 %e A251804 ..1..1....2..3....1..0....0..2....2..3....2..3....2..3....3..2....0..2....1..1 %e A251804 ..2..3....3..3....0..1....0..0....3..2....0..2....0..3....0..1....0..3....3..3 %e A251804 ..0..2....2..3....0..3....3..3....2..3....0..0....1..1....0..3....3..1....2..2 %e A251804 ..2..0....0..2....1..0....3..3....0..1....0..0....0..2....3..2....0..2....3..3 %K A251804 nonn %O A251804 1,1 %A A251804 _R. H. Hardin_, Dec 09 2014