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 A121202 #25 Sep 03 2024 15:03:13
%S A121202 0,14,48,254,1824,13742,102096,745502,5374272,38400590,272709744,
%T A121202 1928498750,13597146720,95668307438,672119557392,4717043931998,
%U A121202 33080342679168,231867574534286,1624598900645040,11379821699045246
%N A121202 a(n) = 12*n + 7^n - 5^n.
%H A121202 Vincenzo Librandi, <a href="/A121202/b121202.txt">Table of n, a(n) for n = 0..1000</a>
%H A121202 <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (14,-60,82,-35).
%F A121202 G.f.: 2*(7*x-74*x^2+211*x^3)/((1-x)^2*(1-5*x)*(1-7*x)). - _Vincenzo Librandi_, Feb 25 2013
%F A121202 a(n) = 14*a(n-1)-60*a(n-2)+82*a(n-3)-35*a(n-4). - _Vincenzo Librandi_, Feb 27 2013
%t A121202 CoefficientList[Series[2 (7 x - 74 x^2 + 211 x^3)/((1-x)^2 (1-5 x)(1-7 x)), {x, 0, 30}], x] (* _Vincenzo Librandi_, Feb 25 2013 *)
%o A121202 (Magma) [7^n - 5^n + 12*n: n in [0..30]]; // _Vincenzo Librandi_, Feb 25 2013
%o A121202 (Magma) I:=[0, 14, 48, 254]; [n le 4 select I[n] else 14*Self(n-1)-60*Self(n-2)+82*Self(n-3)-35*Self(n-4): n in [1..20]]; // _Vincenzo Librandi_, Feb 25 2013
%Y A121202 Cf. A074616.
%K A121202 nonn,easy
%O A121202 0,2
%A A121202 _Mohammad K. Azarian_, Aug 19 2006
%E A121202 Edited by _Ray Chandler_, Sep 06 2006