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 A189746 #32 Jun 02 2025 04:04:19
%S A189746 5,2,20,104,560,3008,16160,86816,466400,2505632,13460960,72316064,
%T A189746 388502240,2087143328,11212721120,60237892256,323614903520,
%U A189746 1738550302112,9339981317600,50177007192224,269564998596320,1448179007366048,7780025034022880,41796483184846496
%N A189746 a(1)=5, a(2)=2, a(n) = 5*a(n-1) + 2*a(n-2).
%H A189746 Vincenzo Librandi, <a href="/A189746/b189746.txt">Table of n, a(n) for n = 1..100</a>
%H A189746 <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (5,2).
%F A189746 G.f.: x*(5-23*x)/(1-5*x-2*x^2). - _Bruno Berselli_, May 24 2011
%t A189746 LinearRecurrence[{5,2},{5,2},40]
%o A189746 (Maxima) a[1]:5$ a[2]:2$ a[n]:=5*a[n-1]+2*a[n-2]$ makelist(a[n], n, 1, 24); /* _Bruno Berselli_, May 24 2011 */
%Y A189746 Cf. A000045, A000079, A105476, A159612, A080040, A135522, A103435, A189732, A189734, A189735, A189736, A189737, A189738, A189739, A189741, A189742, A189743, A189744, A189745, A189747, A189748, A189749.
%K A189746 nonn,easy
%O A189746 1,1
%A A189746 _Harvey P. Dale_, Apr 26 2011