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 A123868 #27 Sep 08 2022 08:45:28 %S A123868 0,4095,531440,16777215,244140624,2176782335,13841287200,68719476735, %T A123868 282429536480,999999999999,3138428376720,8916100448255,23298085122480, %U A123868 56693912375295,129746337890624,281474976710655,582622237229760,1156831381426175,2213314919066160 %N A123868 a(n) = n^12 - 1. %C A123868 a(n) mod 13 = 0 iff n mod 13 > 0; a(A008595(n)) = 12; a(A113763(n)) = 0. %H A123868 T. D. Noe, <a href="/A123868/b123868.txt">Table of n, a(n) for n = 1..1000</a> %H A123868 <a href="/index/Rec#order_13">Index entries for linear recurrences with constant coefficients</a>, signature (13,-78,286,-715,1287,-1716,1716,-1287,715,-286,78,-13,1). %F A123868 From _Chai Wah Wu_, Jun 18 2016: (Start) %F A123868 a(n) = 13*a(n-1) - 78*a(n-2) + 286*a(n-3) - 715*a(n-4) + 1287*a(n-5) - 1716*a(n-6) + 1716*a(n-7) - 1287*a(n-8) + 715*a(n-9) - 286*a(n-10) + 78*a(n-11) - 13*a(n-12) + a(n-13) for n > 12. %F A123868 G.f.: x*(4095 + 478205*x + 10187905*x^2 + 66317979*x^3 + 162513078*x^4 + 162511362*x^5 + 66319266*x^6 + 10187190*x^7 + 478491*x^8 + 4017*x^9 + 13*x^10 - x^11)/(1 - x)^13. (End) %p A123868 seq(n^(12) -1, n=1..20); # _G. C. Greubel_, Aug 08 2019 %t A123868 Range[20]^12 -1 (* _G. C. Greubel_, Aug 08 2019 *) %o A123868 (Magma) [n^12 -1:n in [1..20]]; // _Vincenzo Librandi_, Dec 27 2010 %o A123868 (PARI) vector(20, n, n^12 -1) \\ _G. C. Greubel_, Aug 08 2019 %o A123868 (Sage) [n^12 -1 for n in (1..20)] # _G. C. Greubel_, Aug 08 2019 %o A123868 (GAP) List([1..20], n-> n^12 -1); # _G. C. Greubel_, Aug 08 2019 %Y A123868 Cf. A024010, A008456, A005563, A123865, A123866, A123867. %K A123868 nonn,easy %O A123868 1,2 %A A123868 _Reinhard Zumkeller_, Oct 16 2006