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 A200835 #8 Oct 14 2017 10:46:01 %S A200835 176,846,4108,19930,96690,469116,2276028,11042700,53576350,259938722, %T A200835 1261156090,6118806300,29686880836,144033141554,698811908924, %U A200835 3390456382404,16449625906804,79809371351400,387214626739458 %N A200835 Number of 0..5 arrays x(0..n+1) of n+2 elements without any two consecutive increases or two consecutive decreases. %C A200835 Column 5 of A200838. %H A200835 R. H. Hardin, <a href="/A200835/b200835.txt">Table of n, a(n) for n = 1..210</a> %F A200835 Empirical: a(n) = 6*a(n-1) -6*a(n-2) +3*a(n-3) -5*a(n-4) +3*a(n-5) -2*a(n-6) +a(n-7). %F A200835 Empirical g.f.: 2*x*(88 - 105*x + 44*x^2 - 85*x^3 + 50*x^4 - 33*x^5 + 18*x^6) / (1 - 6*x + 6*x^2 - 3*x^3 + 5*x^4 - 3*x^5 + 2*x^6 - x^7). - _Colin Barker_, Oct 14 2017 %e A200835 Some solutions for n=3 %e A200835 ..3....5....0....4....2....3....2....5....3....1....2....0....0....4....1....3 %e A200835 ..3....4....3....1....1....5....0....1....0....1....3....5....2....5....4....4 %e A200835 ..0....4....0....1....5....3....4....2....5....1....3....4....1....0....4....0 %e A200835 ..0....0....2....4....0....3....2....2....4....3....1....5....1....4....4....0 %e A200835 ..1....1....1....2....0....5....3....2....4....3....1....5....2....0....0....5 %K A200835 nonn %O A200835 1,1 %A A200835 _R. H. Hardin_ Nov 23 2011