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 A304907 #5 May 21 2018 11:27:28
%S A304907 0,1,2,9,16,35,84,161,312,639,1240,2354,4536,8593,16128,30360,56672,
%T A304907 105213,195174,360582,664040,1220730,2238324,4095035,7479552,13636750,
%U A304907 24821108,45114813,81887008,148438211,268763160,486082263,878200416,1585098372,2858378368,5149986275
%N A304907 Expansion of x * (d/dx) 1/(1 - Sum_{k>=1} x^k/(1 + x^k)).
%C A304907 Sum of all parts of all Carlitz compositions (compositions without adjacent equal parts) of n.
%H A304907 <a href="/index/Com#comp">Index entries for sequences related to compositions</a>
%F A304907 a(n) = n*A003242(n).
%t A304907 nmax = 35; CoefficientList[Series[x D[1/(1 - Sum[x^k/(1 + x^k), {k, 1, nmax}]), x], {x, 0, nmax}], x]
%t A304907 a[n_] := a[n] = If[n == 0, 1, Sum[Sum[-(-1)^d, {d, Divisors[k]}] a[n - k], {k, 1, n}]]; Table[n a[n], {n, 0, 35}]
%Y A304907 Cf. A001787, A003242, A048272, A066186, A066189.
%K A304907 nonn
%O A304907 0,3
%A A304907 _Ilya Gutkovskiy_, May 20 2018