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 A023034 #26 Sep 08 2022 08:44:47
%S A023034 1,9,45,165,495,1287,3003,6435,12870,24309,43758,75573,125970,203445,
%T A023034 319770,490149,735471,1081080,1562274,2218788,3108105,4289133,5852925,
%U A023034 7882290,10518255,13871286,18156204,23511345,30260340,38564262,48902997
%N A023034 Number of compositions of n into 9 ordered relatively prime parts.
%H A023034 Marius A. Burtea, <a href="/A023034/b023034.txt">Table of n, a(n) for n = 9..5000</a>
%H A023034 N. J. A. Sloane, <a href="/transforms.txt">Transforms</a>
%F A023034 Moebius transform of C(n-1,8).
%F A023034 G.f.: Sum_{k>=1} mu(k) * x^(9*k) / (1 - x^k)^9. - _Ilya Gutkovskiy_, Feb 05 2020
%p A023034 with(numtheory):
%p A023034 a:= n-> add(mobius(n/d)*binomial(d-1, 8), d=divisors(n)):
%p A023034 seq(a(n), n=9..50); # _Alois P. Heinz_, Feb 05 2020
%t A023034 Table[a[n],{n,9,45}]a[n_]:=DivisorSum[n, Binomial[#-1, 8] MoebiusMu[n/#]&]; Array[a, 37, 9] (* or *) a[n_]:=Sum[Boole[Divisible[n,k]] MoebiusMu[n/k] Binomial[k-1,8],{k,1,n}];Table[a[n],{n,9,45}] (* _Vincenzo Librandi_, Feb 08 2020 *)
%o A023034 (Magma) [&+[MoebiusMu(n div d)*Binomial(d-1,8):d in Divisors(n)]:n in[9..39]]; // _Marius A. Burtea_, Feb 07 2020
%Y A023034 Cf. A000741, A000742, A000743, A023031, A023032, A023033, A023035.
%K A023034 nonn
%O A023034 9,2
%A A023034 _David W. Wilson_