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 A191686 #13 Sep 16 2017 03:31:14
%S A191686 1,1,4,28,271,3351,50478,896848,18362109,425695015,11023082676,
%T A191686 315332380452,9876127761371,336120888377743,12351836713047770,
%U A191686 487443031053702976,20559664804361256953,923012267234425940655,43944912052993796265952,2211595951039098481159300
%N A191686 a(n) = n^(n-1) - (n-1)^(n-1) - ... - 2^(n-1) - 1^(n-1).
%H A191686 Seiichi Manyama, <a href="/A191686/b191686.txt">Table of n, a(n) for n = 1..387</a>
%e A191686 a(1)=1 (=1^0), a(2)=1 (=2^1-1^1), a(3)=4 (=3^2-2^2-1^2).
%p A191686 A191686 := proc(n) n^(n-1)-add( i^(n-1),i=1..n-1) ; end proc:
%p A191686 seq(A191686(n),n=1..20) ; # _R. J. Mathar_, Jun 11 2011
%t A191686 Table[n^(n-1)-Total[Range[n-1]^(n-1)],{n,20}] (* _Harvey P. Dale_, Sep 20 2011 *)
%Y A191686 Cf. A031971, A000169.
%K A191686 nonn
%O A191686 1,3
%A A191686 _Juri-Stepan Gerasimov_, Jun 11 2011
%E A191686 Corrected by _R. J. Mathar_, Jun 11 2011