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 A334706 #16 Jun 20 2020 14:14:30 %S A334706 4,8,20,44,84,140,224,332,472,648,864,1120,1428,1784,2196,2668,3204, %T A334706 3804,4480,5228,6056,6968,7968,9056,10244,11528,12916,14412,16020, %U A334706 17740,19584,21548,23640,25864,28224,30720,33364,36152,39092,42188,45444,48860,52448,56204 %N A334706 Number of collinear triples in a 4 X n rectangular grid. %H A334706 Giovanni Resta, <a href="/A334706/b334706.txt">Table of n, a(n) for n = 1..1000</a> %H A334706 <a href="/index/Rec#order_07">Index entries for linear recurrences with constant coefficients</a>, signature (2,0,-1,-1,0,2,-1). %F A334706 From _Stefano Spezia_, Jun 20 2020: (Start) %F A334706 G.f.: 4*x*(1 + x^2 + 2*x^3 + 2*x^4)/((1 - x)^4*(1 + 2*x + 2*x^2 + x^3)). %F A334706 a(n) = 2*a(n-1) - a(n-3) - a(n-4) + 2*a(n-6) - a(n-7) for n > 7. (End) %Y A334706 A column of A334704. %K A334706 nonn %O A334706 1,1 %A A334706 _N. J. A. Sloane_, Jun 13 2020 %E A334706 Terms a(8) and beyond from _Giovanni Resta_, Jun 20 2020