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 A351421 #16 Feb 16 2022 04:12:07
%S A351421 1,-1,3,-13,77,-576,5219,-55567,680028,-9405302,145067040,-2468571128,
%T A351421 45936991110,-927915150852,20219040931738,-472697857817078,
%U A351421 11801903989774760,-313395752536945568,8819464678850030936,-262185434197432956664,8210080944919085511680
%N A351421 Expansion of e.g.f. -log(1 - log(1 + log(1+x))).
%F A351421 a(n) = T(n,3), T(n,k) = Sum_{j=1..n} Stirling1(n,j) * T(j,k-1), k>1, T(n,1) = (n-1)!.
%t A351421 T[n_, 1] := (n - 1)!; T[n_, k_] := T[n, k] = Sum[StirlingS1[n, j] * T[j, k - 1], {j, 1, n}]; a[n_] := T[n, 3]; Array[a, 21] (* _Amiram Eldar_, Feb 11 2022 *)
%o A351421 (PARI) my(N=40, x='x+O('x^N)); Vec(serlaplace(-log(1-log(1+log(1+x)))))
%o A351421 (PARI) T(n, k) = if(k==1, (n-1)!, sum(j=1, n, stirling(n, j, 1)*T(j, k-1)));
%o A351421 a(n) = T(n, 3);
%Y A351421 Column k=3 of A351420.
%Y A351421 Cf. A000268, A130410.
%K A351421 sign
%O A351421 1,3
%A A351421 _Seiichi Manyama_, Feb 11 2022