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 A014336 #17 Sep 08 2022 08:44:39 %S A014336 0,0,0,6,36,210,1080,5460,26964,132294,645480,3142590,15277680, %T A014336 74222616,360445176,1750067430,8496115740,41243946330,200209950504, %U A014336 971859585804,4717557894060,22899644483430,111157568501760 %N A014336 Three-fold exponential convolution of Fibonacci numbers with themselves. %H A014336 Nathaniel Johnston, <a href="/A014336/b014336.txt">Table of n, a(n) for n = 0..500</a> %H A014336 <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (6,-1,-24,9). %F A014336 (1/5)(3^n*Fibonacci(n) - 3*Fibonacci(2n)). - _Ralf Stephan_, May 14 2004 %F A014336 From _R. J. Mathar_, Jun 10 2013: (Start) %F A014336 G.f.: -6*x^3 / ( (x^2-3*x+1)*(9*x^2+3*x-1) ). %F A014336 a(n) = 6*A014337(n). (End) %p A014336 with(combinat):A014336:=proc(n)return (1/5)*(3^n*fibonacci(n)-3*fibonacci(2*n)):end: %p A014336 seq(A014336(n), n=0..22); # _Nathaniel Johnston_, Apr 18 2011 %o A014336 (Magma) [(1/5)*(3^n*Fibonacci(n) - 3*Fibonacci(2*n)): n in [0..30]]; // _Vincenzo Librandi_, Apr 18 2011 %Y A014336 Cf. A000045. %K A014336 nonn,easy %O A014336 0,4 %A A014336 _N. J. A. Sloane_