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 A096308 #11 May 10 2019 11:14:30
%S A096308 1,2,3,18,25,620,721,24878,158445,1658782,3628801,429976228,479001601,
%T A096308 26820722994,639056694705,10758464202978,20922789888001,
%U A096308 3774016217836154,6402373705728001,1535093032367692372,17443309565597717361,237373353486966539746
%N A096308 a(n) = Sum_{d divides n} (-1)^(n-d)*Stirling1(n,d).
%H A096308 Alois P. Heinz, <a href="/A096308/b096308.txt">Table of n, a(n) for n = 1..450</a>
%p A096308 a:= n-> add(abs(Stirling1(n, d)), d=numtheory[divisors](n)):
%p A096308 seq(a(n), n=1..23); # _Alois P. Heinz_, May 10 2019
%t A096308 f[n_] := Sum[ If[ Mod[n, d] == 0, (-1)^(n - d)StirlingS1[n, d], 0], {d, n}]; Table[ f[n], {n, 20}] (* _Robert G. Wilson v_, Aug 12 2004 *)
%K A096308 easy,nonn
%O A096308 1,2
%A A096308 _Vladeta Jovovic_, Aug 01 2004
%E A096308 More terms from _Robert G. Wilson v_, Aug 12 2004