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 A083327 #11 Jan 05 2021 21:33:00
%S A083327 0,1,7,40,217,1156,6097,31900,165697,855076,4387537,22404460,
%T A083327 113945377,577590196,2919923377,14729076220,74167952257,372944296516,
%U A083327 1873182473617,9399885079180,47135702874337,236224784974036
%N A083327 a(n) = (5^n - 4^n + 3^n - 2^n)/2.
%C A083327 Binomial transform of A053154 (with leading zero).
%H A083327 <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (14,-71,154,-120).
%F A083327 G.f.: x(1-7x+13x^2)/((1-2x)(1-3x)(1-4x)(1-5x)).
%F A083327 E.g.f.: exp(5x) - exp(4x) + exp(3x) - exp(2x).
%F A083327 a(n) = 14*a(n-1) - 71*a(n-2) + 154*a(n-3) - 120*a(n-4), n > 3. - _Harvey P. Dale_, Apr 04 2013
%t A083327 Table[(5^n-4^n+3^n-2^n)/2,{n,0,30}] (* or *) LinearRecurrence[{14,-71,154,-120},{0,1,7,40},30] (* _Harvey P. Dale_, Apr 04 2013 *)
%Y A083327 Cf. A083328.
%K A083327 easy,nonn
%O A083327 0,3
%A A083327 _Paul Barry_, Apr 27 2003