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 A280797 #18 Nov 20 2024 04:18:23
%S A280797 0,0,5,182,13107,1627604,310968905,84777884106,31274997412295,
%T A280797 15009463529699912,9090909090909090909,6783562448903313426110,
%U A280797 6115142092568526471803195,6552380728090615475599972572,8231779712749862388415318790417,11984441202055255416780710220336914
%N A280797 a(n) = (n^n - 1)*(n^n + 1)/(n + 1).
%F A280797 a(n) = A117812(n)/(n + 1).
%e A280797 a(0) = 0 because (0^0 - 1)*(0^0 + 1)/(0 + 1) = 0,
%e A280797 a(1) = 0 because (1^1 - 1)*(1^1 + 1)/(1 + 1) = 0,
%e A280797 a(2) = 5 because (2^2 - 1)*(2^2 + 1)/(2 + 1) = 5.
%t A280797 Table[If[n == 0, 0, (n^n - 1) (n^n + 1)/(n + 1)], {n, 0, 15}] (* _Michael De Vlieger_, Jan 09 2017 *)
%o A280797 (Magma) [(n^(2*n)-1)/(n+1): n in [0..15]];
%Y A280797 Cf. A000312, A081216, A117812, A179897.
%K A280797 nonn,easy
%O A280797 0,3
%A A280797 _Juri-Stepan Gerasimov_, Jan 08 2017
%E A280797 Offset changed to 0 by _Georg Fischer_, Jul 15 2024