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 A267470 #7 Feb 05 2018 09:36:08 %S A267470 8,64,484,3592,26440,193852,1418740,10378144,75944464,556295860, %T A267470 4080955516,29994246136,220942982968,1631599880428,12082194095812, %U A267470 89736369169168,668588308469152,4997804102441956,37486765952804428 %N A267470 Number of length-n 0..7 arrays with no following elements larger than the first repeated value. %C A267470 Column 7 of A267471. %H A267470 R. H. Hardin, <a href="/A267470/b267470.txt">Table of n, a(n) for n = 1..210</a> %F A267470 Empirical: a(n) = 43*a(n-1) -798*a(n-2) +8358*a(n-3) -54201*a(n-4) +224427*a(n-5) -589112*a(n-6) +936452*a(n-7) -807408*a(n-8) +282240*a(n-9). %F A267470 Conjectures from _Colin Barker_, Feb 05 2018: (Start) %F A267470 G.f.: 4*x*(2 - 70*x + 1029*x^2 - 8253*x^3 + 39228*x^4 - 112119*x^5 + 185785*x^6 - 160106*x^7 + 53244*x^8) / ((1 - x)*(1 - 2*x)*(1 - 3*x)*(1 - 4*x)*(1 - 5*x)*(1 - 6*x)*(1 - 7*x)^2*(1 - 8*x)). %F A267470 a(n) = (-980 - 147*2^(2+n) - 245*2^(1+2*n) - 490*3^n - 245*2^(2+n)*3^n - 588*5^n + 7818*7^n + 735*8^n + 120*7^n*n) / 5880. %F A267470 (End) %e A267470 Some solutions for n=6: %e A267470 ..1....4....2....2....4....2....6....4....6....6....6....0....6....2....2....2 %e A267470 ..0....7....6....5....6....7....3....6....3....0....7....2....3....5....0....7 %e A267470 ..6....0....0....0....1....7....1....3....2....4....3....7....1....0....3....5 %e A267470 ..1....3....0....1....4....5....5....6....1....3....2....7....7....7....7....0 %e A267470 ..2....6....0....0....1....5....1....3....2....6....7....7....5....3....2....5 %e A267470 ..3....6....0....7....1....1....4....1....2....1....7....6....7....6....3....5 %Y A267470 Cf. A267471. %K A267470 nonn %O A267470 1,1 %A A267470 _R. H. Hardin_, Jan 15 2016