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 A238291 #19 Oct 21 2023 09:31:14
%S A238291 1,0,6,6,0,0,4,6,4,0,8,6,8,0,0,6,2,0,2,0,6,0,6,6,0,0,4,6,4,0,8,6,8,0,
%T A238291 0,6,2,0,2,0,6,0,6,6,0,0,4,6,4,0,8,6,8,0,0,6,2,0,2,0,6,0,6,6,0,0,4,6,
%U A238291 4,0,8,6,8,0,0,6,2,0,2,0,6,0,6,6,0,0
%N A238291 Final digit of real part of (n+n*i)^n.
%C A238291 Starting from a(2) the sequence is periodic with period length 20. - _Giovanni Resta_, Feb 23 2014
%H A238291 Vincenzo Librandi, <a href="/A238291/b238291.txt">Table of n, a(n) for n = 1..1000</a>
%H A238291 <a href="/index/Rec#order_20">Index entries for linear recurrences with constant coefficients</a>, signature (0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1).
%t A238291 re[n_, b_] := Mod[b + Re@PowerMod[(n + n I), n, b], b];
%t A238291 Table[re[n, 10], {n, 100}]
%Y A238291 Cf. A238292, A056849.
%K A238291 nonn,base
%O A238291 1,3
%A A238291 _José María Grau Ribas_, Feb 22 2014